Thermoplastic elastomer for cold and wet applications

ABSTRACT

Thermoplastic compositions including component C, an ethylene/α-olefin interpolymer wherein the interpolymer has a Mooney Viscosity (ML 1+4, 125° C.) greater than, or equal to 55 and a ΔHf greater than, or equal to 36 J/g; and component D, a high density polyethylene (HDPE) are provided. In particular, the thermoplastic compositions are characterized by the ethylene/α-olefin interpolymer which is an ethylene/a-olefin/diene interpolymer having a rheology ratio (V0.1/V 100) at 190° C. greater than, or equal to 25. Also are provided the articles comprising the thermoplastic compositions.

REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of U.S. Provisional Application No.61/263,262, filed Nov. 20, 2009, the disclosure of which is incorporatedherein by reference.

FIELD OF INVENTION

The invention relates to a thermoplastic elastomer composition rich inethylene/α-olefin polymer content or propylene-α-olefin content, andmore particularly to thermoplastic elastomer profiles for use in coldand/or wet applications.

BACKGROUND OF THE INVENTION

Gaskets are used in a variety of applications, for example inappliances, such as refrigerators and freezers, each requiring aflexible gasket for sealing the area between the door and appliancebody. One of the most commonly used materials for the production ofgaskets is polyvinyl chloride (PVC). PVC gaskets become brittle at lowtemperatures and cracking becomes a problem, and installation at lowertemperatures is also difficult. Also, an unpleasant odor is presentduring compounding and extrusion of PVC, and when the finished gasketsare removed from packaging prior to installation. Moreover, PVC is notconsidered an environmentally friendly material because it involves theuse of the following: vinyl chloride monomer production, phthalateplasticizers, heat stabilizers, and processing lubricants that maycontain heavy metals. In addition, PVC-based gaskets, or other products,may give rise to disposal concerns as well as potential release of toxicmaterials in the event of incineration. Therefore, there is a need for amaterial to replace PVC-based profiles, particularly those used in largehome appliances such as refrigerator and freezer gaskets, washingmachines, dryers and dishwashers, and which satisfies the requiredspecifications, and has improved processability and environmentalfriendliness. Other applications of such polymeric materials couldinclude, for example, molded articles, overmolded articles, and tubing.

Profiles made of thermoplastics, manufactured by the profile extrusionprocess, are known. The design of compositions of thermoplasticelastomers (TPE) used for profiles demands that several properties bebalanced. These include low viscosity at processing shear rates, abilityto freeze quickly as the profile leaves the die so dimensional stabilitycan be maintained, a certain compression set for elastic recovery undertransportation and use conditions, ability to heat weld, and a certainsoftness for better sealing properties. Production of TPEs for profileapplications has required rheological modification steps, such asperoxide modification of the thermoplastic elastomer or dynamicvulcanization, or use of expensive ingredients such as styrene blockcopolymer (SBC)-rich compounds, in order to balance the required end-useproperties. Therefore, there remains a need for a TPE for profile usethat meets all of the specifications to replace PVC-based profiles,while simplifying production and design of the TPEs.

SUMMARY OF THE INVENTION

One embodiment of the invention provides a first thermoplastic elastomercomposition comprising at least one elastomeric polymer, component A,selected from the group of ethylene/α-olefin interpolymers andpropylene/α-olefin interpolymers; at least one semi-crystalline polymer,component B, selected from the group of polypropylene homopolymers,propylene/ethylene copolymers and high density polyethylene; at leastone oil; and at least one filler, wherein the thermoplastic elastomercomposition is characterized by a Shape Retention Index (SRI) less thanor equal to 1.6 at 10000 Pa s, and less than 4.5 at 1000 Pa s forcompositions with TMA at 1000 μm greater than 85° C.

Another embodiment of the invention provides a second compositioncomprising: i) component C, an ethylene/α-olefin interpolymer whereinthe interpolymer has a Mooney Viscosity (ML 1+4, 125° C.) greater than,or equal to, 55 and a ΔHf greater than, or equal to, 36 J/g; and ii)component D, a high density polyethylene (HDPE).

DETAILED DESCRIPTION OF THE INVENTION

The Inventive Thermoplastic Elastomer Compositions

The invention provides a first thermoplastic elastomer compositioncomprising at least one elastomeric polymer, component A, selected fromthe group consisting of ethylene/α-olefin interpolymers andpropylene/α-olefin interpolymers; at least one semi-crystalline polymer,component B, selected from the group consisting of polypropylenehomopolymers, propylene/ethylene copolymers and high densitypolyethylene; at least one oil; and at least one filler, wherein thethermoplastic elastomer composition is characterized by an SRI less thanor equal to 1.6 at 10000 Pa-s, and less than 4.5 at 1000 Pa-s forcompositions with TMA at 1000 μm greater than 85° C.

The invention also provides a second composition comprising at least oneethylene/α-olefin interpolymer, component C, which optionally comprisesa third comonomer, wherein the interpolymer has a Mooney Viscositygreater than, or equal to, 55 and ΔHf greater than, or equal to, 36 J/g;and component D, a high density polyethylene (HDPE).

Certain embodiments of the inventive first and second compositionssatisfy certain relationships between tan delta (tan δ) and viscosity(referred to as shape retention index or “SRI”) over an extendedtemperature range.

Some embodiments of the inventive first and second compositions providepolymer compositions meeting specific tensile modulus, elongation,compression set at −10° C. and 40° C., UV resistance, weight reductionon heating, Vicat softening temperature, water resistance, split tearresistance, anti-microbial resistance, weight loss on cooling/heatingcycle, odor, weld strength, chemical and oil resistance, tactile feel,and crystallization temperature, as may be specified by various OEMs ofrelevant end-use appliances.

Some embodiments of the inventive first and second compositions do notutilize formulated thermoplastic vulcanates or rheology-modified,reactive-extruded blends, or TPEs rich in styrenic polymers. That is,the inventive first and second compositions do not contain more than 50wt % thermoplastic vulcanate and/or styrenic polymers based on the totalthermoplastic elastomer composition weight.

Ethylene/α-Olefin Interpolymers Useful in Components A and C

Components A and C, in some embodiments, each independently comprises anethylene/α-olefin copolymers, or blends thereof.

Components A and C, in some embodiments of the invention, eachindependently comprises an ethylene/α-olefin-diene interpolymers, orblends thereof.

Components A and C, in some embodiments of the invention, compriseblends of one or more ethylene/α-olefin copolymers and one or moreethylene/α-olefin-diene interpolymers.

Ethylene/α-olefin interpolymers, including both ethylene/α-olefincopolymers and ethylene/α-olefin-diene interpolymers, useful in variousembodiments of the invention may have a ΔHf greater than, or equal to,36 J/g. All values of ΔHf greater than, or equal to, 36 J/g aredisclosed and included herein. For example, the ethylene/α-olefininterpolymers useful in the invention, alternatively, may have, forexample, a ΔHf greater than, or equal to, 37 J/g; or, in thealternative, greater than, or equal to, 38 J/g.

Ethylene/α-olefin interpolymers useful in components A and C may have aMooney Viscosity greater than, or equal to, 55. All values of MooneyViscosity of greater than, or equal to, 55 are included and disclosedherein. For example, ethylene/α-olefin interpolymers useful in theinvention may have a Mooney viscosity of greater than or equal to 55; inthe alternative, greater than or equal to 57; in the alternative,greater than or equal to 59; or in the alternative, greater than orequal to 60; or in the alternative, greater than or equal to 61.

α-olefin monomers useful in the ethylene/α-olefin copolymers andinterpolymers of components A and C may be selected, in certainembodiments, from the group of C₃-C₂₀ α-olefins. Preferred α-olefins foruse in certain embodiments of the invention are designated by theformula CH₂CHR*, where R* is a linear or branched alkyl group of from 1to 12 carbon atoms. Examples of suitable α-olefins include, but are notlimited to, propylene, isobutylene, 1-butene, 1-pentene, 1-hexene,4-methyl-1-pentene, and 1-octene. A particularly preferred α-olefin ispropylene

Suitable dienes for use in the ethylene/α-olefin-diene interpolymers ofcomponents A and C, include conjugated or non-conjugated, straight orbranched chain-, cyclic- or polycyclic-dienes comprising from 4 to 20carbons. Preferred dienes include 1,4-pentadiene, 1,4-hexadiene,5-ethylidene-2-norbornene, dicyclopentadiene, cyclohexadiene, and5-butylidene-2-norbornene.

In some embodiments, the ethylene/α-olefin-diene interpolymer has amolecular weight distribution (MWD) from 2 to 4. All values andsub-ranges from 2 to 4 are included and disclosed herein; for example,ethylene/α-olefin/diene interpolymer may have an upper limit of MWD of2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, 3.8 or 4 and an MWD lower limit of2, 2.2, 2.4, 2.6, 2.8, 3, 3.2, 3.4, 3.6, 3.8. The MWD of theethylene/α-olefin/diene interpolymer may be from 2 to 4; in thealternative, from 2.5 to 3.5; in the alternative, from 2.8 to 3.8; or inthe alternative, from 2.1 to 3.9.

In some embodiments, the ethylene/α-olefin-diene interpolymer has a %crystallinity (% Cry) from 13 to 20%, by weight. All values andsub-ranges from 13% Cry to 20% Cry are included and disclosed herein;for example the ethylene/α-olefin/diene interpolymer % Cry may have anupper limit of 14%, 15%, 16%, 17%, 18%, 19% or 20% by weight, and anethylene/α-olefin-diene interpolymer % Cry lower limit of 13%, 14%, 15%,16%, 17%, 18%, or 19% by weight. The % Cry of theethylene/α-olefin/diene interpolymers useful in the invention may befrom 13% to 20% by weight; in the alternative, from 14% to 19% byweight; in the alternative, from 15% to 18% by weight; or in thealternative, from 16% to 20% by weight.

In other embodiments, the ethylene/α-olefin-diene polymers have anethylene content of from 50% to 70% by weight, a propylene content from20% to 49% by weight, and a nonconjugated diene content from 1% to 10%by weight, all weight percentages based upon the total weight of thepolymer. All values and sub-ranges from 50 to 70 wt % ethylene contentin the ethylene/α-olefin/diene interpolymer are included and disclosedherein. For example, the ethylene/α-olefin/diene interpolymer may have alower limit of 50, 55, 60, or 65 wt % ethylene and an upper limit of 55,60, 65, or 70 wt % ethylene. All values and sub-ranges of 20 to 49 wt %propylene content in the ethylene/α-olefin/diene interpolymer areincluded and disclosed herein. For example, the ethylene/α-olefin/dienepolymer may have a lower limit of 20, 25, 30, 35, 40 or 45 wt %propylene and an upper limit of 25, 30, 35, 40 or 49 wt % propylene. Allvalues and sub-ranges of 1 to 10 wt % diene content in theethylene/α-olefin/diene interpolymer are included and disclosed herein.For example, the ethylene/α-olefin/diene interpolymer may have a lowerlimit of 1, 3, 5, 7 or 9 wt % diene and an upper limit of 2, 4, 6, 8 or10 wt % diene.

In some embodiments of the invention, the ethylene/α-olefin/dieneinterpolymer has a rheology ratio (V0.1/V100), at 190° C., greater thanor equal to 25. All values of the ethylene/α-olefin/diene interpolymerrheology ratio of greater than or equal to 25 are included and disclosedherein; for example the ethylene/α-olefin/diene interpolymer rheologyratio, at 190° C., may alternatively be greater than or equal to 30; inthe alternative, greater than or equal to 35; in the alternative,greater than or equal to 39; in the alternative, greater than or equalto 41; in the alternative, greater than or equal to 45; or in thealternative, greater than or equal to 50.

In one embodiment, the ethylene/α-olefin interpolymer is an EPDM.

In one embodiments of the inventive composition, components A and Ccomprise an ethylene/propylene/diene (EPDM) interpolymer, or blendthereof.

In some embodiments, the EPDM interpolymer contains from 20% to 80% byweight of ethylene, from 19% to 70% by weight of a higher α-olefin, andfrom 1% to 10% by weight of a nonconjugated diene. The more preferredhigher α-olefins are propylene and 1-butene. The more preferred polyenesare ethylidene norbornene, 1,4-hexadiene, and dicyclopentadiene.

Examples of representative EPDM interpolymers for use include Nordel IP4770R/P, Nordel IP 4760, Nordel IP 4785 and Nordel IP 3760P HydrocarbonRubbers available from Dow Chemical. Keltan polymers available from DSMElastomers Americas, Baton Rouge, La., VISTALON EP(D)Methylene/propylene rubber of EPDM interpolymers available fromExxonMobil Chemical or ROYALENE EPDM available from Lion Copolymers,LLC. Particularly useful are EPDM with a Mooney Viscosity greater thanequal to 50.

In a preferred embodiment, the ethylene/α-olefin/diene interpolymer isnot oil extended.

In a preferred embodiment, the ethylene/α-olefin/diene interpolymer isin the form of free-flowing pellets. As used herein, free-flowing refersto the ability of the pellets (of typical polymer pellet sizes) to moveor flow at ambient conditions, without adhering together to form largermasses.

In one embodiment, the ethylene/α-olefin/diene interpolymer is formedusing a single site catalyst. In a further embodiment, the single sitecatalyst is selected from a metallocene catalyst, a constrained geometrycatalyst, or a post metallocene catalyst. In a further embodiment, thesingle site catalyst is selected from a constrained geometry catalyst,or a post metalllocene catalyst.

In one embodiment, the ethylene/α-olefin/diene interpolymer is formedusing a constrained geometry catalyst.

In one embodiment, the ethylene/α-olefin/diene interpolymer is formedusing a post metalllocene catalyst.

In one embodiment, the ethylene/α-olefin/diene interpolymer has amolecular weight distribution (MWD) less than 3.5, preferably less than3.2, and more preferably less than 3.1.

In one embodiment, the ethylene/α-olefin/diene interpolymer is dilutedwith a minor amount of oil and/or process additive, such that the oiland/or additive level is less than 33% of the weight of the polymer inthe pre-compounded state.

In a preferred embodiment, the ethylene/α-olefin/diene interpolymer isnot diluted with an oil or process additive in the pre-compounded state.

In one embodiment, the ethylene/α-olefin/diene interpolymer comprises atleast two ethylene/α-olefin/diene interpolymers, and preferably twointerpolymers. In one embodiment, at least one interpolymer has acrystallization temperature (Tc) less than 35° C., preferably less than30° C., and more preferably less than 25° C., and the overallethylene/α-olefin/diene interpolymer has a crystallization temperature(Tc) greater than 20° C., preferably greater than 25° C., and morepreferably greater than 28° C. In one embodiment, at least oneinterpolymer has a Mooney Viscosity (ML 1+4, 125° C.) from 30 to 100,preferably 40 to 90, and the overall ethylene/α-olefin/dieneinterpolymer has a Mooney Viscosity (ML 1+4, 125° C.) from 50 to 100,preferably 50 to 90. In one embodiment, at least one interpolymer has aMWD from 1.5 to 3, and the overall ethylene/α-olefin/diene interpolymerhas a MWD from 2 to 3.5. In one embodiment, each interpolymer is anEPDM, and preferably the diene is 5-ethylidene-2-norbornene (ENB). Asdiscussed herein, the ethylene/α-olefin/diene interpolymer may comprisea combination of these embodiments.

In one embodiment, the ethylene/α-olefin/diene interpolymer is anin-reactor blend of at least two polymers, and preferably two polymers.

In one embodiment, the ethylene/α-olefin/diene interpolymer is apost-reactor blend of at least two polymers, and preferably twopolymers.

In a preferred embodiment, the ethylene/α-olefin/diene interpolymer isan EPDM.

In a further embodiment, the diene is ENB.

The ethylene/α-olefin/diene interpolymer may comprise a combination oftwo or more embodiments as described herein.

An ethylene/α-olefin interpolymer may comprise a combination of two ormore embodiments as described herein.

An ethylene/α-olefin copolymer may comprise a combination of two or moreembodiments as described herein.

An ethylene/α-olefin-diene interpolymer may comprise a combination oftwo or more embodiments as described herein.

Ethylene/α-Olefin Multiblock Copolymers Useful in Component A

As used herein, the terms “olefin block copolymers” and “OBC” meanolefin multiblock, excluding olefin diblock, copolymers.

In some embodiments, component A comprises olefin block copolymers,e.g., ethylene multiblock copolymers, such as those described in theInternational Publication No. WO2005/090427 and U.S. Publication2006-199930A1, the disclosures of which are incorporated herein byreference. Such olefin block copolymers may be an ethylene/α-olefininterpolymer: (a) having a M_(w)/M_(n) from about 1.7 to about 3.5, atleast one melting point, T_(m), in degrees Celsius, and a density, d, ingrams/cubic centimeter (g/cc), wherein the numerical values of T_(m) andd corresponding to the relationship: T_(m)>−2002.9+4538.5(d)−2422.2(d)²;or (b) having a M_(w)/M_(n) from about 1.7 to about 3.5, and beingcharacterized by a heat of fusion, ΔHf in Joules per gram (J/g), and adelta quantity, ΔT, in degrees Celsius defined as the temperaturedifference between the tallest DSC peak and the tallest CRYSTAF peak,wherein the numerical values of ΔT and ΔHf having the followingrelationships: ΔT>−0.1299(ΔHf)+62.81 for ΔHf greater than zero and up to130 J/g, and ΔT≧48° C. for ΔHf greater than 130 J/g, wherein the CRYSTAFpeak being determined using at least 5 percent of the cumulativepolymer, and if less than 5 percent of the polymer having anidentifiable CRYSTAF peak, then the CRYSTAF temperature being 30° C.; or(c) being characterized by an elastic recovery, Re, in percent at 300percent strain and 1 cycle measured with a compression-molded film ofthe ethylene/α-olefin interpolymer, and having a density, d (g/cc),wherein the numerical values of Re and d satisfying the followingrelationship when ethylene/α-olefin interpolymer being substantiallyfree of a cross-linked phase: Re>1481-1629(d); or (d) having a molecularfraction which elutes between 40° C. and 130° C. when fractionated usingTREF, characterized in that the fraction having a molar comonomercontent of at least 5 percent higher than that of a comparable randomethylene interpolymer fraction eluting between the same temperatures,wherein said comparable random ethylene interpolymer having the samecomonomer(s) and having a melt index, density, and molar comonomercontent (based on the whole polymer) within 10 percent of that of theethylene/α-olefin interpolymer; or (e) having a storage modulus at 25°C., G′ (25° C.), and a storage modulus at 100° C., G′ (100° C.), whereinthe ratio of G′ (25° C.) to G′ (100° C.) being in the range of about 1:1to about 9:1.

The ethylene/α-olefin interpolymer may also: (a) have a molecularfraction which elutes between 40° C. and 130° C. when fractionated usingTREF, characterized in that the fraction having a block index of atleast 0.5 and up to about 1 and a molecular weight distribution,M_(w)/M_(n), greater than about 1.3; or (b) have an average block indexgreater than zero and up to about 1.0 and a molecular weightdistribution, M_(w)/M_(n), greater than about 1.3. Such olefin blockcopolymers are commercially available from The Dow Chemical Company,under the tradename INFUSE Olefin Block Copolymers.

An ethylene/α-olefin multiblock copolymer may comprise a combination oftwo or more embodiments as described herein.

Propylene/α-Olefin Interpolymers Useful in Component A

In some embodiments of the first thermoplastic elastomer composition,component A comprises one or more propylene/α-olefin interpolymers.

Although ethylene is not generally characterized as an α-olefin, as usedherein the term propylene/α-olefin interpolymers in connection withcomponent A, includes propylene-ethylene interpolymers, as furthercharacterized below.

Such propylene/α-olefin copolymers are further described in details inthe U.S. Pat. Nos. 6,960,635 and 6,525,157, incorporated herein byreference. Such propylene/α-olefin copolymers are commercially availablefrom The Dow Chemical Company, under the tradename VERSIFY Elastomersand Plastomers, or from ExxonMobil Chemical Company, under the tradenameVISTAMAXX.

In one embodiment, the propylene/α-olefin copolymer, is characterized ashaving substantially isotactic propylene sequences. “Substantiallyisotactic propylene sequences” means that the sequences have anisotactic triad (mm) measured by ¹³CNMR of greater than about 0.85; inthe alternative, greater than about 0.90; in another alternative,greater than about 0.92; and in another alternative, greater than about0.93. Isotactic triads are well-known in the art and are described in,for example, U.S. Pat. No. 5,504,172 and International Publication No.WO 00/01745, which refer to the isotactic sequence in terms of a triadunit in the copolymer molecular chain, determined by ¹³CNMR spectra.

The propylene/α-olefin copolymer may have a melt flow rate in the rangeof from 0.1 to 25 g/10 minutes, measured in accordance with ASTM D-1238(at 230° C./2.16 Kg). All individual values and sub-ranges from 0.1 to25 g/10 minutes are included herein and disclosed herein; for example,the melt flow rate can be from a lower limit of 0.1 g/10 minutes, 0.2g/10 minutes, or 0.5 g/10 minutes to an upper limit of 25 g/10 minutes,15 g/10 minutes, 10 g/10 minutes, 8 g/10 minutes, or 5 g/10 minutes. Forexample, the propylene/α-olefin copolymer may have a melt flow rate inthe range of 0.1 to 10 g/10 minutes; or in the alternative, thepropylene/α-olefin copolymer may have a melt flow rate in the range of0.2 to 10 g/10 minutes.

The propylene/α-olefin copolymer has a crystallinity in the range from 1percent by weight (a heat of fusion of 2 Joules/gram (J/g)) to 30percent by weight (a heat of fusion of 50 Joules/gram). All individualvalues and sub-ranges from 1 percent by weight (a heat of fusion of 2Joules/gram) to 30 percent by weight (a heat of fusion of 50Joules/gram) are included herein and disclosed herein; for example, thecrystallinity can be from a lower limit of 1 percent by weight (a heatof fusion of 2 Joules/gram), 2.5 percent (a heat of fusion of 4Joules/gram), or 3 percent (a heat of fusion of 5 Joules/gram) to anupper limit of 30 percent by weight (a heat of fusion of 50Joules/gram), 24 percent by weight (a heat of fusion of 40 Joules/gram),15 percent by weight (a heat of fusion of 24.8 Joules/gram) or 7 percentby weight (a heat of fusion of 11 Joules/gram). For example, thepropylene/α-olefin copolymer may have a crystallinity in the range offrom 1 percent by weight (a heat of fusion of 2 Joules/gram) to 24percent by weight (a heat of fusion of 40 Joules/gram); or in thealternative, the propylene/α-olefin copolymer may have a crystallinityin the range of from 1 percent by weight (a heat of fusion of 2Joules/gram) to 15 percent by weight (a heat of fusion of 24.8Joules/gram); or in the alternative, the propylene/α-olefin copolymermay have a crystallinity in the range of from 1 percent by weight (aheat of fusion of 2 Joules/gram) to 7 percent by weight (a heat offusion of 11 Joules/gram); or in the alternative, the propylene-α-olefincopolymer may have a crystallinity in the range of from 1 percent byweight (a heat of fusion of 2 Joules/gram) to 5 percent by weight (aheat of fusion of 8.3 Joules/gram). The crystallinity is measured viaDSC method, as described herein. The propylene/α-olefin copolymercomprises units derived from propylene and units derived from one ormore α-olefin comonomers. Exemplary comonomers utilized in thepropylene/α-olefin copolymer are C₄ to C₁₀ α-olefins; for example, C₄,C₆ and C₈ α-olefins. A particularly preferred polyethylene/α-olefin ofcomponent A is propylene-ethylene copolymer.

The propylene/α-olefin copolymer comprises from 1 to 40 percent byweight of one or more α-olefin comonomers, including as discussed above,ethylene. All individual values and sub-ranges from 1 to 40 weightpercent are included herein and disclosed herein; for example, thecomonomer content can be from a lower limit of 1 weight percent, 3weight percent, 4 weight percent, 5 weight percent, 7 weight percent, or9 weight percent to an upper limit of 40 weight percent, 35 weightpercent, 30 weight percent, 27 weight percent, 20 weight percent, 15weight percent, 12 weight percent, or 9 weight percent. For example, thepropylene/α-olefin copolymer comprises from 1 to 35 percent by weight ofone or more α-olefin comonomers; or in the alternative, thepropylene/α-olefin copolymer comprises from 1 to 30 percent by weight ofone or more α-olefin comonomers; or in the alternative, thepropylene/α-olefin copolymer comprises from 3 to 27 percent by weight ofone or more α-olefin comonomers; or in the alternative, thepropylene/α-olefin copolymer comprises from 3 to 20 percent by weight ofone or more α-olefin comonomers; or in the alternative, thepropylene/α-olefin copolymer comprises from 3 to 15 percent by weight ofone or more α-olefin comonomers.

In some embodiments of the invention, the propylene/α-olefin copolymeris propylene/ethylene wherein the ethylene is present in amounts from 9to 15 wt % of the total propylene/ethylene copolymer weight. Allindividual values and sub-ranges from 9 to 16 weight percent areincluded herein and disclosed herein; for example, the comonomer contentcan be from a lower limit of 9, 10, 11, 12, 13 or 14 weight percent toan upper limit of 10, 11, 12, 13, 14, or 15 weight percent. For example,the propylene/ethylene copolymer may comprise in a weight percentderived from ethylene of from 9 to 15 wt %, or in the alternative, from10 to 14 wt %, or in the alternative, from 11 to 13 wt %.

The propylene/α-olefin copolymer has a molecular weight distribution(MWD), defined as weight average molecular weight divided by numberaverage molecular weight (M_(w)/M_(n)) of 3.5 or less; in thealternative 3.0 or less; or in another alternative from 1.8 to 3.0.

Such propylene/α-olefin copolymers are further described in details inthe U.S. Pat. Nos. 6,960,635 and 6,525,157, incorporated herein byreference. Such propylene/α-olefin copolymers are commercially availablefrom The Dow Chemical Company, under the tradename VERSIFY Elastomersand Plastomers, or from ExxonMobil Chemical Company, under the tradenameVISTAMAXX.

In one embodiment, the propylene-α-olefin copolymers are furthercharacterized as comprising (A) between 60 and less than 100, preferablybetween 80 and 99 and more preferably between 85 and 99, weight percentunits derived from propylene, and (B) between greater than zero and 40,preferably between 1 and 20, more preferably between 4 and 16, and evenmore preferably between 4 and 15, weight percent units derived from atleast one of ethylene and/or a C₄C₁₀ α-olefin; and containing an averageof at least 0.001, preferably an average of at least 0.005 and morepreferably an average of at least 0.01, long chain branches/1000 totalcarbons, wherein the term long chain branch refers to a chain length ofat least one (1) carbon more than a short chain branch, and whereinshort chain branch refers to a chain length of two (2) carbons less thanthe number of carbons in the comonomer. For example, apropylene/1-octene interpolymer has backbones with long chain branchesof at least seven (7) carbons in length, but these backbones also haveshort chain branches of only six (6) carbons in length. The maximumnumber of long chain branches in the propylene interpolymer is notcritical to the definition of this embodiment of the instant invention,but typically it does not exceed 3 long chain branches/1000 totalcarbons. Such propylene-α-olefin copolymers are further described indetails in the U.S. Provisional Patent Application No. 60/988,999;International Publication WO2009/067337A1, and EP0964890B1, each ofwhich is incorporated herein by reference.

A propylene/α-olefin interpolymer may comprise a combination of two ormore embodiments as described herein.

Polypropylene Homopolymers and Propylene/Ethylene Copolymers Useful inComponent B

Embodiments of the inventive first thermoplastic elastomer compositionalso include at least one semi-crystalline polymer, component B,selected from the group consisting of polypropylene homopolymers,propylene/ethylene copolymers and high density polyethylene. As furtherdetailed below, the propylene/ethylene copolymers useful in component Bhave different structure and properties from those of thepropylene/α-olefin interpolymers useful in components A and C.

In one embodiment, Component B is a polypropylene homopolymer.

In one embodiment, the polypropylene homopolymer has a melting point(Tm), as determined by DSC, greater than, or equal to, 125° C., orgreater than, or equal to, 130° C., greater than, or equal to, 135° C.,greater than, or equal to, 140° C.

In one embodiment, the polypropylene homopolymer has a heat of fusion(ΔHf), as determined by DSC, greater than, or equal to, 75 J/g, orgreater than, or equal to, 80 J/g, greater than, or equal to, 85 J/g.

In one embodiment, the polypropylene homopolymer has a weight averagemolecular weight (M_(w)) within the range having an upper limit of5,000,000 g/mol, or 500,000 g/mol, and a lower limit of 10,000 g/mol, or50,000 g/mol.

In one embodiment, the polypropylene homopolymer has a molecular weightdistribution M_(w)/M_(n) (MWD), sometimes referred to as a“polydispersity index” (PDI), within the range having an upper limit of40, or 30, or 20, or 10, and a lower limit of 2, or 3, or 4, or 5.

In one embodiment, Component B is a propylene/ethylene copolymer.

In one embodiment, the propylene/ethylene copolymer comprises greaterthan, or equal to, 90 wt %, or greater than, or equal to, 92 wt %, orgreater than, or equal to, 94 wt %, or greater than, or equal to, 96 wt%, or greater than, or equal to, 98 wt % of polymerized propylene, basedon the weight of the copolymer.

In one embodiment, the propylene/ethylene copolymer comprises less than,or equal to, 10 wt %, or less than, or equal to, 8 wt %, or less than,or equal to, 6 wt %, or less than, or equal to, 4 wt %, or less than, orequal to, 2 wt % of polymerized ethylene, based on the weight of thecopolymer.

In one embodiment, the propylene/ethylene copolymer has a melting point(Tm), as determined by DSC, greater than, or equal to, 125° C., orgreater than, or equal to, 130° C., greater than, or equal to, 135° C.,greater than, or equal to, 140° C.

In one embodiment, the propylene/ethylene copolymer has a heat of fusion(ΔHf), as determined by DSC, greater than, or equal to, 75 J/g, orgreater than, or equal to, 80 J/g, greater than, or equal to, 85 J/g.

In one embodiment, the propylene/ethylene copolymer has a weight averagemolecular weight (M_(w)) within the range having an upper limit of5,000,000 g/mol, or 500,000 g/mol, and a lower limit of 10,000 g/mol, or50,000 g/mol.

In one embodiment, the propylene/ethylene copolymer has a molecularweight distribution M_(w)/M_(n) (MWD), sometimes referred to as a“polydispersity index” (PDI), within the range having an upper limit of40, or 30, or 20, or 10, and a lower limit of 2, or 3, or 4, or 5.

The propylene homopolymer may be formed by the homopolymerization ofpropylene in a single stage or multiple stage reactors.

The propylene/ethylene copolymer may be formed by copolymerizingpropylene and ethylene in a single stage or multiple stage reactors.

Polymerization methods for preparing the polypropylene homopolymer orpropylene/ethylene copolymer include high pressure, slurry, gas, bulk,solution phase, and combinations thereof. Catalyst systems includetraditional Ziegler-Natta catalysts and single-site metallocene catalystsystems. In one embodiment, the catalyst used has a high isospecificity.Each polymerization may be carried out by a continuous or batch process,and may include the use of chain transfer agents, scavengers, or othersuch additives well known to those skilled in the art. The polypropylenehomopolymer or propylene/ethylene copolymer may also contain one or moreadditives, such as flow improvers, nucleators, and antioxidants.

A polypropylene homopolymer may comprise a combination of two or moreembodiments as described herein.

A propylene/ethylene copolymer may comprise a combination of two or moreembodiments as described herein.

HDPE Useful in Components B and D

Some embodiments of the inventive first thermoplastic elastomercomposition also include at least one high density polyethylene.

Embodiments of the inventive second composition comprise at least oneHDPE.

The properties of the high density polyethylene (HDPE) useful in certainembodiments of the invention vary depending upon the desiredapplication. The molecular weight of the HDPE for use in certainembodiments of the invention varies depending upon the application, butmay be indicated using a melt flow measurement I₂ is inverselyproportional to the molecular weight of the polymer. The higher themolecular weight, the lower the I₂, although the relationship is notlinear.

High-density polyethylene useful in components B and D of certainembodiments of the invention may have a density in the range from 0.94to 0.96 g/cc. All individual values and sub-ranges from 0.94 to 0.96g/cc are included herein and disclosed herein; for example, thehigh-density polyethylene composition may have a lower limit density of0.94 g/cc, 0.945 g/cc, 0.95 or 0.955 g/cc and an upper limit density of0.945 g/cc, 0.949 g/cc, 0.955 g/cc or 0.96 g/cc. For example, thehigh-density polyethylene may have a density in the range of 0.940 to0.950 g/cc; or in the alternative, from 0.95 to 0.96 g/cc; or in thealternative, from 0.945 to 0.960 g/cc.

In one embodiment, the high-density polyethylene may have an I₂ from 1to 50 g/10 min. All values and sub-ranges from 1 to 50 g/10 min aredisclosed and included herein; for example, the high-densitypolyethylene composition may have an I₂ lower limit of 1, 10, 20, 30, 40or 45 g/10 min and an upper limit of 5, 15, 25, 35, 45, or 50 g/10 min.The high-density polyethylene may have an I₂ from 1 to 50 g/10 min; orin the alternative, from 20 to 40 g/10 min; or in the alternative, from30 to 43 g/10 min; in the alternative, from 5 g/10 min to 30 g/10 min;or in the alternative, from 5 to 46 g/10 min.

Molecular weight distribution (Mw/Mn) of the HDPE can be narrow orbroad, e.g., Mw/Mn from 2 to as high as 40. All individual ranges from 2to 40 are included and disclosed herein: for example, the HDPE may havea lower limit of Mw/Mn of 2, 5, 10, 13, 23 or 36 and an upper limit ofMw/Mn of 5, 12, 20, 27, 33, 39, or 40.

In those embodiments of the invention comprising an HDPE in component Bor D, the HDPE may be present in an amount from 30 to 100 PHR, based onthe weight of the ethylene/α-olefin interpolymer. All values andsub-ranges from 30 to 100 PHR are included and disclosed herein; forexample the HDPE may be present at an upper limit of 40, 50, 60, 70, 80,90 or 100 PHR and at a lower limit of 30, 40, 50, 60, 70, 80, or 90 PHR.The amount of HDPE may range, for example, from 30 to 70 PHR; in thealternative, from 30 to 60 PHR; in the alternative, from 30 to 40 PHR;in the alternative from 40-80 PHR; in the alternative, from 60 to 90PHR; or in the alternative from 60 to 85 PHR.

The HDPE may be produced by any process including metallocene, Cr andZiegler-Natta catalyst processes. Any conventional ethylenehomopolymerization or copolymerization reactions may be employed toproduce the high-density polyethylene useful in embodiments of theinvention. Such conventional ethylene homopolymerization orcopolymerization reactions include, but are not limited to, gas phasepolymerization, slurry phase polymerization, liquid phasepolymerization, and combinations thereof using conventional reactors,e.g. gas phase reactors, loop reactors, stirred tank reactors, and batchreactors.

An HDPE may comprise a combination of two or more embodiments asdescribed herein.

Alternative Embodiments of the Thermoplastic Elastomer Compositions

One embodiment of the first thermoplastic elastomer compositioncomprises at least one elastomeric polymer, component A, selected fromthe group of ethylene/α-olefin interpolymers and propylene/α-olefininterpolymers, at least one semi-crystalline polymer, component B,selected from the group of polypropylene homopolymers,propylene/ethylene copolymers and high density polyethylene, at leastone oil, and at least one filler wherein the first thermoplasticelastomer composition is characterized by an SRI less than or equal to1.5 at 10000 Pa-s, and less than 4.5 at 1000 Pa-s for compositions withTMA greater than 85° C.

In an alternative embodiment, the first thermoplastic elastomercomposition provides a composition in accordance with any of thepreceding embodiments, except that the composition is furthercharacterized by a hardness in the range of 40-85 Shore A, tensilestrength between 2 and 8 MPa, elongation>400%, and compression set at40° C. from 30 to 75% as measured by ISO 815, Type B method.

In an alternative embodiment, the first thermoplastic elastomercomposition provides a composition in accordance with any of thepreceding embodiments, except that the composition the component A isone or more EPDM.

In an alternative embodiment, the first thermoplastic elastomercomposition provides a composition in accordance with any of thepreceding embodiments, except that the component A is one or more olefinblock copolymer, in combination in an amount from 20 wt % to 50 wt %based on the total weight of the thermoplastic elastomer composition.

In an alternative embodiment, the first thermoplastic elastomercomposition provides a composition in accordance with any of thepreceding embodiments, except that component A, is an ethylene/α-olefincopolymer.

In an alternative embodiment, the first thermoplastic elastomercomposition provides a composition in accordance with any of thepreceding embodiments, except that component A is an ethylene/α-olefininterpolymer, and the semi-crystalline polymer, component B, is a highdensity polyethylene.

In some preferred embodiments of the first thermoplastic elastomercompositions, the elastomeric polymer, component A, is anethylene/α-olefin interpolymer, and the semi-crystalline polymer,component B, is a high density polyethylene.

In an alternative embodiment, the first thermoplastic elastomercomposition has an SRI less than, or equal to, 1.5 at 10000 Pa s.

In alternative embodiments of the first thermoplastic elastomercomposition, the elastomeric polymer, component A, is ethylene/α-olefininterpolymer, and the semi-crystalline polymer, component B, is apolypropylene homopolymer.

In alternative embodiments of the first thermoplastic elastomercomposition, the elastomeric polymer, component A, is ethylene/α-olefininterpolymer, and the semi-crystalline polymer, component B, is one ormore semi-crystalline propylene/ethylene copolymers.

In alternative embodiments of the first thermoplastic elastomercomposition, the addition of an oil and/or filler is optional.

In alternative embodiments of the first thermoplastic elastomercompositions, the elastomeric polymer, component A, is apropylene/α-olefin interpolymer, and the semi-crystalline polymer,component B, is a high density polyethylene.

In alternative embodiments of the first thermoplastic elastomercomposition, the elastomeric polymer, component A, is apropylene/α-olefin interpolymer, and the semi-crystalline polymer,component B, is a polypropylene homopolymer.

In alternative embodiments of the first thermoplastic elastomercomposition, the elastomeric polymer, component A, is apropylene/α-olefin interpolymer, and the semi-crystalline polymer,component B, is one or more propylene/ethylene copolymers.

In some embodiments of the invention, the first thermoplastic elastomercompositions are inventive compositions comprising an elastomercomprising an ethylene/α-olefin interpolymer (optionally furthercomprising a diene) or propylene/α-olefin interpolymer, with rheologyratios measured at 190° C. (viscosity at 0.1 rad/s to viscosity at 100rad/s (V0.1/V100)) greater than 25. In certain aspects, the inventivecompositions provided herein comprise at least one thermoplasticvulcanizates (TPVs) and/or hydrogenated styrenic block copolymers(“HSBC,” such as SEBS, SEPS or SEEPS), for providing an improvement incompression set at elevated temperatures in certain compositions, apropylene-based polymer (such as, homopolypropylene (hPP) or randomcopolymer of propylene (RCP)), or a low density polyethylene (LDPE) orhigh density polyethylene (HDPE).

One embodiment of the inventive first and second compositions is furthercharacterized by a hardness in the range of 40-85 Shore A, tensilestrength from 2 to 8 MPa, elongation>400%, and compression set at 40° C.from 30 to 75%. In some embodiments of the inventive first thermoplasticelastomer composition, the component A is one or more EPDM, incombination, in the amount from 20 wt % to 50 wt % based on the totalweight of the thermoplastic elastomer composition.

In some embodiments of the inventive first and second compositions, theethylene/α-olefin/diene interpolymer has a rheology ratio (V0.1/V100),at 190° C., greater than, or equal to 25.

In some embodiments of the inventive first and second compositions, theethylene/α-olefin interpolymer is an ethylene/propylene interpolymer.

In some embodiments of the inventive first and second compositions, theethylene/propylene interpolymer has a rheology ratio (V0.1N100), at 190°C., greater than, or equal to 22.

In some embodiments of the inventive first and second compositions, theHDPE has an I₂ from 1 to 50 g/10 min, preferably from 5 g/10 min to 30g/10 min.

In a preferred embodiment, the inventive first and second compositionsdo not comprise a vulcanization agent. Vulcanization agents includeperoxides, azo compounds, phenols, azides, aldehyde-amine reactionproducts, substituted ureas, substituted guanidines; substitutedxanthates; substituted dithiocarbamates; sulfur-containing compounds,such as thiazoles, imidazoles, sulfonamides, thiuramidisulfides,paraquinonedioxime, dibenzoparaquinonedioxime, sulfur; silanes. SeeEncyclopedia of Chemical Technology, Vol. 17, 2nd edition, IntersciencePublishers, 1968; also Organic Peroxides, Daniel Seem, Vol. 1,Wiley-Interscience, 1970); and C. P. Park, “Polyolefin Foam” Chapter 9,Handbook of Polymer Foams and Technology, D. Klempner and K. C. Frisch,eds., Hanser Publishers, New York (1991), pages 198-204. See also U.S.Pat. Nos. 7,741,408; 6,506,842; 5,869,591 and 5,977,271. Each referenceis incorporated herein by reference.

In a preferred embodiment, an inventive first or second composition doesnot comprise a free radical coagent. The free radical coagent is amonomer or low molecular weight polymer having two or more functionalgroups with high response to free radicals. Typically, these functionalgroups are either methacrylate, allyl or vinyl. Free radical coagentsinclude diallyl terephthalate, triallylcyanurate, triallylisocyanurate,1,2 polybutadiene, divinyl benzene, trimethylolpropane trimethacrylate,polyethylene glycol dimethacrylate, ethylene glycol dimethacrylate,pentaerythritol triacrylate, allyl methacrylate, N N′-m-phenylenebismaleimide, toluene bismaleimide-p-quinone dioxime, nitrobenzene,diphenylguanidine.

In one embodiment of the inventive first or second composition, eachcomprises ethylene/α-olefin interpolymer and HDPE. In one embodiment theethylene/α-olefin interpolymer is present in an amount greater than theamount of the HDPE.

In one embodiment of the inventive first or second composition, theweight ratio of the ethylene/α-olefin interpolymer to the HDPE is from 2to 5, preferably from 2.2 to 4, and more preferably from 2.5 to 3.5.

In one embodiment, the inventive first or second composition comprisesethylene/α-olefin/diene interpolymer and HDPE. In one embodiment of thefirst or second compositions, the ethylene/α-olefin/diene interpolymeris EPDM. In a further embodiment the diene is ENB.

In one embodiment of the inventive first or second composition, theethylene/α-olefin/diene interpolymer is present in an amount greaterthan the amount of the HDPE. In one embodiment theethylene/α-olefin/diene interpolymer is EPDM. In a further embodimentthe diene is ENB.

In one embodiment of the inventive first or second composition, theweight ratio of the ethylene/α-olefin/diene interpolymer to the HDPE isfrom 2 to 5, preferably from 2.2 to 4, more preferably from 2.5 to 3.5.In a further embodiment, the ethylene/α-olefin/diene interpolymer is anEPDM. In a further embodiment, the diene is ENB.

In one embodiment, the inventive first or second composition comprisesethylene/α-olefin copolymer and HDPE. In a further embodiment, theα-olefin is a C3-C10 α-olefin, and preferably selected from 1-octene,1-hexene, 1-butene or propylene.

In one embodiment the ethylene/α-olefin copolymer is present in anamount greater than the amount of the HDPE. In a further embodiment, theα-olefin is a C3-C10 α-olefin, and preferably selected from 1-octene,1-hexene, 1-butene or propylene.

In one embodiment, the weight ratio of the ethylene/α-olefin copolymerto the HDPE is from 2 to 5, preferably from 2.2 to 4, more preferablyfrom 2.5 to 3.5. In a further embodiment, the α-olefin is a C3-C10α-olefin, and preferably selected from 1-octene, 1-hexene, 1-butene orpropylene.

In some embodiments of the inventive first thermoplastic elastomercomposition, the component A is one or more olefin block copolymer, incombination, in the amount from 20 wt % to 50 wt % based on the totalweight of the thermoplastic elastomer composition.

In some embodiments of the inventive second composition, the component Cis one or more olefin block copolymer, in combination, in the amountfrom 20 wt % to 50 wt % based on the total weight of the thermoplasticelastomer composition.

In some embodiments of the inventive first thermoplastic elastomercomposition, the elastomeric polymer, component A, comprises a diene.

In some embodiments of the inventive second composition, the elastomericpolymer, component C, comprises a diene.

In some embodiments of the inventive first thermoplastic elastomercomposition, the elastomeric polymer, component A, is anethylene/α-olefin interpolymer, and the semi-crystalline polymer,component B, is a high density polyethylene (HDPE).

In some embodiments of the inventive first or second compositions, theethylene/α-olefin interpolymer has a ΔHf greater than, or equal to, 36J/g, preferably greater than, or equal to, 38 J/g.

In some embodiments of the first or second inventive composition, theethylene/α-olefin interpolymer is an ethylene/α-olefin/dieneinterpolymer.

In some embodiments of the inventive first thermoplastic elastomercomposition, the component A is one or more EPDM, in combination in anamount from 20 wt % to 50 wt % based on the total weight of thethermoplastic elastomer composition.

In some embodiments of the inventive first and second compositions, theHDPE present in an amount from 30 to 100 PHR, based on the weight of theethylene/α-olefin interpolymer.

The invention further provides a second composition comprising: i)component C, an ethylene/α-olefin interpolymer, optionally comprising athird comonomer, wherein the interpolymer has a Mooney Viscosity (ML1+4, 125° C.) greater than, or equal to, 55 and ΔHf greater than, orequal to, 36 J/g; and ii) component D, a high density polyethylene(HDPE).

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat wherein the second composition is further characterized by an SRIless than or equal to 1.5 at 10000 Pa-s, and less than 4.5 at 1000 Pa-sfor compositions with TMA greater than 85° C.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, excepttha component C has a MWD less than 4.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, excepttha the ethylene/α-olefin interpolymer is an ethylene/α-olefin/dieneinterpolymer.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the ethylene/α-olefin/diene interpolymer has a rheology ratio(V0.1/V100), at 190° C., greater than, or equal to 25.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the ethylene/α-olefin interpolymer is an ethylene/propyleneinterpolymer.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the ethylene/propylene interpolymer has a rheology ratio(V0.1/V100), at 190° C., greater than, or equal to 22.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the HDPE has an I₂ from 1 to 50 g/10 min, or from 5 to 40 g/10 min,or from 10 to 20 g/10 min.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the HDPE is present in an amount from 30 to 100 PHR, based on theweight of the ethylene/α-olefin interpolymer.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the second composition further comprises an oil.

In an alternative embodiment, the second composition provides acomposition in accordance with any of the preceding embodiments, exceptthat the second composition further comprises a filler.

The invention further provides an article comprising at least onecomponent formed from the composition of any one of the precedingembodiments.

In one embodiment, the inventive article has a tack force less than, orequal to, 0.012 N.

In an alternative embodiment, the inventive article is in accordancewith any of the preceding embodiments, except that the article has acompression set, at 70° C., less than 70 percent, as measured by ASTMD-395.

Some embodiments of the inventive second composition further comprise anoil.

Some embodiments of the inventive second composition further comprise afiller.

Some embodiments of the inventive article have a tack force less than,or equal to, 0.012 N.

Some embodiments of the inventive article have a compression set, at 70°C., less than 70 percent.

Embodiments of the invention provide polyolefin-based inventivecompositions, further including additives and fillers to produce arheological behavior to replace PVC-based profiles while meeting theperformance properties demanded by the intended end-use application.

One embodiment of the inventive second composition is furthercharacterized by a hardness in the range of 40-85 Shore A, tensilestrength from 2 to 8 MPa, elongation>400%, and compression set at 40° C.from 30 to 75%.

One embodiment of the second composition comprises at least oneethylene/α-olefin interpolymer, component C, wherein the interpolymerhas a Mooney Viscosity greater than, or equal to, 55 and ΔHf greaterthan, or equal to, 36 J/g; and component D, at least one high densitypolyethylene (HDPE).

One embodiment of the second composition is characterized by an SRI lessthan or equal to 1.6 at 10000 Pa-s, and less than 4.5 at 1000 Pa-s forcompositions with TMA at 1000 μm greater than 85° C.

One embodiment of the second composition comprises a component c havinga MWD less than 3.

One embodiment of the second composition comprises a component c havinga MWD less than 2.5.

One embodiment of the second composition comprises a component c havinga MWD less than 2.

One embodiment of the second composition comprises a component c havinga MWD in the range from 1 to 3.

One embodiment of the second composition comprises a component c havinga MWD in the range from 1.5 to 3.

Additives

In some embodiments, the inventive compositions further comprise an oil.Oils useful in embodiments of the invention include, for example, aparaffinic oil, aromatic oil, napththenic oil, hydrogenated (white) oil(such as, Kaydol oil), vegetable and animal oil and their derivatives,petroleum derived oils or a combination thereof. When present, the oilpresent may be in an amount from 50 to 200 PHR (based on the weight ofthe ethylene/α-olefin interpolymer). All values and sub-ranges from 50to 200 PHR are included and disclosed herein; for example, the oilamount may have a lower limit of 50, 70, 90, 110, 130, 150, 170, or 190PHR and an upper limit of 60, 80, 100, 120, 140, 160, 180 or 200 PHR.The oil may be present in an amount from 50 to 200 PHR; in thealternative, from 50 to 130 PHR; in the alternative, from 70 to 180 PHR;in the alternative, from 80 to 120 PHR; or in the alternative, from 130to 190 PHR.

A variety of additives, optionally, may be used in compositions of theinvention. The additives include surface tension modifiers, flameretardants, scratch and mar modifying additives, anti-block agents, slipadditives (including a wide variety of primary amides, secondary amidesand secondary bis-amides, such as oleamides, erucamides andstearamides), lubricants, antimicrobial agents (such as organometallics,isothazolones, organosulfurs and mercaptans); antioxidants (such asphenolics, secondary amines, phosphites and thioesters); antistaticagents (such as quaternary ammonium compounds, amines, and ethoxylated,propoxylated or glycerol compounds); hydrolytic stabilizers; lubricants(such as fatty acids, fatty alcohols, esters, fatty amides, metallicstearates, paraffinic and microcrystalline waxes, silicones andorthophosphoric acid esters); mold release agents (such as fine-particleor powdered solids, soaps, waxes, silicones, polyglycols and complexesters such as trimethylolpropane tristearate or pentaerythritoltetrastearate); pigments, dyes and colorants; plasticizers (such asesters of dibasic acids (or their anhydrides) with monohydric alcoholssuch as o-phthalates, adipates and benzoates); heat stabilizers (such asorganotin mercaptides, an octyl ester of thioglycolic acid and a bariumor cadmium carboxylate); ultraviolet light stabilizers (such as ahindered amine, an o-hydroxy-phenylbenzotriazole, a 2-hydroxy,4-alkoxyenzophenone, a salicylate, a cyanoacrylate, a nickel chelate anda benzylidene malonate and oxalanilide); and zeolites, molecular sievesand other known deodorizers. One example of a hindered phenolicantioxidant is Irganox™ 1076 antioxidant, available from BASF. Each ofthe above additives, if used, typically does not exceed 5 wt %, based ontotal composition weight, and may be from 0.001 to 2 wt %; preferablyfrom 0.01 to 1 wt % and more preferably from 0.1 to 5 wt %.

In some embodiments of the invention, a composition further comprisespolydimethysiloxane. When present, polydimethylsiloxane may be presentin an amount from 0 to 0.5 wt %, based on the total weight of thethermoplastic elastomer composition.

The inventive compositions disclosed herein may comprise at least onefiller which can be used to adjust, for example, volume, weight, costs,and/or technical performance. Non-limiting examples of fillers useful invarious embodiments of the invention include talc, calcium carbonate,chalk, calcium sulfate, clay, kaolin, silica, glass, fumed silica, mica,wollastonite, feldspar, aluminum silicate, calcium silicate, alumina,hydrated alumina such as alumina trihydrate, glass microsphere, ceramicmicrosphere, thermoplastic microsphere, barite, wood flour, glassfibers, carbon fibers, marble dust, cement dust, magnesium oxide,magnesium hydroxide, antimony oxide, zinc oxide, barium sulfate,titanium dioxide, titanates and combinations thereof. In someembodiments, the filler is barium sulfate, talc, calcium carbonate,silica, glass, glass fiber, alumina, titanium dioxide, or a mixturethereof. In other embodiments, the filler is talc, calcium carbonate,barium sulfate, glass fiber or a mixture thereof. The fillers disclosedin U.S. Pat. No. 6,103,803 and Zweifel Hans et al., “Plastics AdditivesHandbook,” Hanser Gardner Publications, Cincinnati, Ohio, 5th edition,Chapter 17, pages 901-948 (2001), both of which are incorporated hereinby reference, may also be used in various embodiments of the invention.

The amount of the filler in the inventive composition may be from 20 to200 PHR (based on weight of ethylene/α-olefin interpolymer). All valuesand sub-ranges from 20 to 200 PHR are disclosed and included herein; forexample, the filler may be present from an upper limit of 30, 60, 90,120, 150, 170 or 200 PHR and from a lower limit of 20, 50, 80, 110, 140,170 or 190 PHR. The filler may be present in an amount ranging from 20to 100 PHR; in the alternative, from 40 to 180 PHR; in the alternative,from 60 to 150 PHR; or in the alternative, from 100 to 130 PHR.

In some embodiments, the inclusion of an adsorptive inorganic additivemay improve the odor properties of the products provided herein thoughno odor issues exist with the specific examples mentioned herein. Theaddition of an odor absorber additive such as charcoal, calciumcarbonate or magnesium oxide in the range from about 0.1 to about 3weight percent, or about 0.5 to about 2 weight percent, based on thetotal composition, is effective in eliminating odors.

In other embodiments, the inventive compositions disclosed hereinoptionally comprise at least one UV stabilizer that may prevent orreduce the degradation of the inventive compositions by UV radiations.Any UV stabilizer known to a person of ordinary skill in the art may beadded to the inventive compositions disclosed herein. Non-limitingexamples of suitable UV stabilizers include benzophenones,benzotriazoles, aryl esters, oxanilides, acrylic esters, formamidines,carbon black, hindered amines, nickel quenchers, hindered amines,phenolic antioxidants, metallic salts, zinc compounds and combinationsthereof. Where used, the amount of the UV stabilizer in the inventivecomposition can be from about greater than 0 to about 5 wt %, from about0.01 to about 3 wt %, from about 0.1 to about 2 wt %, or from about 0.1to about 1 wt % of the total weight of the inventive composition. SomeUV stabilizers have been described in Zweifel Hans et al., “PlasticsAdditives Handbook,” Hanser Gardner Publications, Cincinnati, Ohio, 5thedition, Chapter 2, pages 141-426 (2001), which is incorporated hereinby reference.

Optionally, the inventive compositions disclosed herein can comprise atleast one lubricant. In general, the lubricant can be used, inter alia,to modify the rheology of the molten inventive compositions, to improvethe surface finish of molded articles, and/or to facilitate thedispersion of fillers or pigments. Any lubricant known to a person ofordinary skill in the art may be added to the inventive compositionsdisclosed herein. Non-limiting examples of suitable lubricants includefatty alcohols and their dicarboxylic acid esters, fatty acid esters ofshort-chain alcohols, fatty acids, fatty acid amides, metal soaps,oligomeric fatty acid esters, fatty acid esters of long-chain alcohols,montan waxes, polyethylene waxes, polypropylene waxes, natural andsynthetic paraffin waxes, fluoropolymers and combinations thereof. Insome embodiments, lubricants comprise an organopolysiloxane. In someembodiments, the organopolysiloxane can have an average molecular weightnot less than 40,000 and a viscosity of at least 50.000 cSt.

Where used, the amount of the lubricant in the inventive composition maybe from greater than 0 to 5 wt %; in the alternative, from 0.1 to 4 wt%; or in the alternative, from 0.1 to 3 wt % of the total weight of theinventive composition. Lubricants useful in various embodiments of theinvention are disclosed in Zweifel Hans et al., “Plastics AdditivesHandbook,” Hanser Gardner Publications, Cincinnati, Ohio, 5th edition,Chapter 5, pages 511-552 (2001), the disclosure of which is incorporatedherein by reference.

Optionally, the inventive compositions can include an anti-microbialagent to impede and/or limit the growth of organisms typicallyencountered in cold and/or wet applications, including bacteriostaticand fungistatic compounds. For example and not limiting anti-microbialagents useful in the invention, any one or combination of anti-microbialagents available from The Dow Chemical Company (Midland, Mich.) underthe name VINYZENE™, which include blends ofdichloro-octyl-isothiazolone; 10,10′-oxybisphenoxarsine;octyl-isothiazolone; and trichlorophenoxyphenol. In a preferredembodiment, a blend of zinc pyritione andn-butyl-1,2-benzisothiazonlin-3-one available from PolyChemAlloy(Lenoir, N.C.) and sold under the name PolySept™ 2003ZV-HF may be usedin the inventive compositions.

Optionally, the inventive compositions may include additives to improveabrasion resistance. For example and without limiting the abrasionresistance additive useful in the invention, the polydimethylsiloxanecompositions disclosed in U.S. Pat. No. 5,902,854, the disclosure ofwhich is incorporated herein by reference, may be used in certainembodiments of the inventive compositions.

In certain aspects, the inventive compositions comprise at least onethermoplastic vulcanizates (TPVs), hydrogenated styrenic blockcopolymers (such as SEBS, or styrene-ethylene ethylene propylene-styrene(SEEPS)), or a combination thereof but not to exceed more than 50 wt %of the total elastomer content of the composition. Thermoplasticelastomers are rubber-like materials that, unlike conventionalvulcanized rubbers, can be processed and recycled like thermoplasticmaterials. When the thermoplastic elastomer contains a vulcanizedrubber, it may also be referred to as a thermoplastic vulcanizate (TPV).TPVs are thermoplastic elastomers with a chemically cross-linked rubberyphase, produced by dynamic vulcanization. One measure of this rubberybehavior is that the material will retract to less than 1.5 times itsoriginal length within one minute, after being stretched at roomtemperature to twice its original length and held for one minute beforerelease (ASTM D1566). Another measure is found in ASTM D412, for thedetermination of tensile set. The materials are also characterized byhigh elastic recovery, which refers to the proportion of recovery afterdeformation and may be quantified as percent recovery after compression.A perfectly elastic material has a recovery of 100% while a perfectlyplastic material has no elastic recovery. Yet another measure is foundin ASTM D395, for the determination of compression set.

One example of a commercial TPV is SATOPRENE™ thermoplastic rubber whichis manufactured by Advanced Elastomer Systems and is a mixture ofcrosslinked EPDM (“XL-EPDM”) particles in a crystalline polypropylenematrix. Another example is VYRAM™, consisting of a mixture ofpolypropylene and natural rubber, marketed by Advanced ElastomerSystems. Other suitable elastomers include KRATON™, a brand of styreneblock copolymer (SBC) marketed by KRATON Polymers, and DYNAFLEX™, athermoplastic elastomer marketed by GLS Corporation and which is madewith KRATON™ polymer.

The ingredients of the inventive compositions, i.e., theethylene/α-olefin interpolymer, the at least one other polymercomponent, such as the elastomer (e.g., TPV,styrene/ethylene-butene/styrene (SEBS) copolymers), the polyolefin, suchas hPP, RCP, LDPE, or HDPE and the optional additives, fillers and oilcan be mixed or blended using methods known to a person of ordinaryskill in the art, preferably methods that can provide a substantiallyhomogeneous distribution of the polyolefin and/or the additives in theethylene/α-olefin interpolymer. Non-limiting examples of suitableblending methods include melt blending, solvent blending, extruding, andthe like.

In some embodiments, physical blending devices that provide dispersivemixing, distributive mixing, or a combination of dispersive anddistributive mixing can be useful in preparing homogenous blends. Bothbatch and continuous methods of physical blending can be used.Non-limiting examples of batch methods include those methods usingmixing equipment available from Brabender (e.g., BRABENDER PREPCENTERT™, available from C. W. Brabender Instruments, Inc., SouthHackensack, N.J.) or BANBURY™ internal mixing and roll milling(available from Farrel Company, Ansonia, Conn.) equipment. Non-limitingexamples of continuous methods include single screw extruding, twinscrew extruding, disk extruding, reciprocating single screw extruding,and pin barrel single screw extruding. In some embodiments, theadditives can be added into an extruder through a feed hopper or feedthroat during the extrusion of the ethylene/α-olefin interpolymer, thepolyolefin or the inventive composition. The mixing or blending ofpolymers by extrusion has been described in C. Rauwendaal, “PolymerExtrusion”, Hanser Publishers, New York, N.Y., pages 322-334 (1986),which is incorporated herein by reference.

When one or more additives are required in the inventive compositions,the desired amounts of the additives can be added in one charge ormultiple charges to the ethylene/α-olefin interpolymer, the polyolefinor the inventive composition. Furthermore, the addition can take placein any order. In some embodiments, the additives are first added andmixed or blended with the ethylene/α-olefin interpolymer, and then theadditive-containing interpolymer is blended with the polyolefin. Inother embodiments, the additives are first added and mixed or blendedwith the polyolefin and then the additive-containing polyolefin isblended with the ethylene/α-olefin interpolymer. In further embodiments,the ethylene/α-olefin interpolymer is blended with the polyolefin firstand then the additives are blended with the inventive composition.

The first thermoplastic elastomer composition may comprise a combinationof two or more embodiments as described herein.

The second composition may comprise a combination of two or moreembodiments as described herein.

Articles using the Inventive Compositions

The invention further provides an article comprising at least onecomponent formed from an inventive composition. Articles which may beproduced from the inventive composition include, for example, gaskets,profiles (including, for example, profiles used for refrigerators and/orfreezers), molded articles, overmolded articles, sheeting, and tubing.

Some embodiments of an inventive article have a compression set, at 70°C., less than 70 percent; in the alternative, less than 65%; or in thealternative, less than 60%.

In one embodiment, the article is a gasket.

In another embodiment, the article is a profile.

Definitions

The term “composition,” as used herein, includes a mixture of materialswhich comprise the composition, as well as reaction products anddecomposition products formed from the materials of the composition.

The term “polymer,” as used herein, refers to a polymeric compoundprepared by polymerizing monomers, whether of the same or a differenttype. The generic term polymer thus embraces the term homopolymer(employed to refer to polymers prepared from only one type of monomer,with the understanding that trace amounts of impurities can beincorporated into the polymer structure), and the term interpolymer asdefined hereinafter.

The term “interpolymer,” as used herein, refers to polymers prepared bythe polymerization of at least two different types of monomers. Thegeneric term interpolymer thus includes copolymers (employed to refer topolymers prepared from two different types of monomers), and polymersprepared from more than two different types of monomers.

The term, “ethylene/α-olefin interpolymer,” as used herein, refers to aninterpolymer that comprises, in polymerized form, a majority amount ofethylene monomer (based on the weight of the interpolymer), and at leastone α-olefin.

The term, “ethylene/α-olefin copolymer,” as used herein, refers to acopolymer that comprises, in polymerized form, a majority amount ofethylene monomer (based on the weight of the copolymer), and anα-olefin, as the only two monomer types.

The term, “propylene/α-olefin interpolymer,” as used herein, refers toan interpolymer that comprises, in polymerized form, a majority amountof propylene monomer (based on the weight of the interpolymer), and atleast one α-olefin.

The term, “propylene/α-olefin copolymer,” as used herein, refers to acopolymer that comprises, in polymerized form, a majority amount ofpropylene monomer (based on the weight of the copolymer), and anα-olefin, as the only two monomer types.

The term, “propylene/ethylene copolymer,” as used herein, refers to acopolymer that comprises, in polymerized form, a majority amount ofpropylene monomer (based on the weight of the copolymer), and ethylene,as the only two monomer types.

The terms “comprising,” “including,” “having,” and their derivatives,are not intended to exclude the presence of any additional component,step or procedure, whether or not the same is specifically disclosed. Inorder to avoid any doubt, all compositions claimed through use of theterm “comprising” may include any additional additive, adjuvant, orcompound, whether polymeric or otherwise, unless stated to the contrary.In contrast, the term, “consisting essentially of” excludes from thescope of any succeeding recitation any other component, step orprocedure, excepting those that are not essential to operability. Theterm “consisting of” excludes any component, step or procedure notspecifically delineated or listed.

The term “elastomer,” as used herein, refers any melt-processablepolymer blend or copolymer in which a continuous elastomeric phasedomain is reinforced by dispersed hard (glassy or crystalline) phasedomains that act as junction points over a limited range of temperature.

The term “thermoplastic,” as used herein, refers to a material that canbe repeatedly made molten (soft) and solidified (hard) through heatingand cooling, respectively.

The term “semi-crystalline polymer,” as used herein, refers to polymershaving regions of crystalline molecular structure and amorphous regions.

The term “elastomeric polymer,” as used herein, refers to athermoplastic elastomer.

The terms “blend,” “polymer blend,” and like terms, as used herein, meana composition of two or more polymers. Such a blend may or may not bemiscible. Such a blend may or may not be phase separated. Such a blendmay or may not contain one or more domain configurations, as determinedfrom transmission electron spectroscopy, light scattering, x-rayscattering, and any other method known in the art.

The term “pre-compounded,” as used herein, refers to the polymer used tomake a polymer formulation, prior to any post reactor compounding ormodification of such polymer. Such a polymer may contain small levels offugitive process oils from processing equipment or from additiveslurries, yet still be considered as not containing any oil. In the casewhere oil is intentionally added to the polymer prior to post reactorcompounding or modification, the oil amount is determined relative tothe weight of the polymer. For a “25% oil containing polymer,” a 1 kgsample would comprise 0.2 kg of oil and 0.80 kg of polymer.

The polymers designated as “free-flowing” do not preclude the use of asurface additive such as talc or polyethylene powder to enhance thefree-flowing nature of the product in use.

Test Methods

Test methods utilized in characterizing the components of the inventiveand comparative examples include the following tests.

Test samples (except for the inventive and comparative examples shown inTable 11) were made on a fully intermeshing co-rotating twin screwextruder manufactured by Krupp Werner Pfleiderer Corporation (ModelZSK-25, a 25-mm screw diameter having a length to diameter ratio of48:1). The extruder was equipped with two-hole strand die, water bathand pelletizer to produce resin in pellet form. The materials werestarve-fed into the extruder using screw type powder feeders. Theextruder conditions were zone 1 through zone 7 were 140° C., 190° C.,190° C., 190° C., 190° C., 190° C., 190° C., respectively, and 180° C.at the die. RPM of 500 was used with water chiller temperature of 10° C.Examples in Table 11 were processed using the conditions shown in Table12.

Except for the inventive and comparative examples shown in Table 11, allsamples used for TMA, DMS, Shore A hardness, NOBI, compression set, SRI,tensile strength and elongation at break, and tack force were injectionmolded plaques were injection molded on an Arburg 370C-80 ton injectionmolder using the 4 inch by 6 inch by 0.125 inch (10.16 cm by 15.24 cm by0.32 cm) tool with a flat barrel profile of 440F (and for the examplesin Table 11 using a flat barrel profile of 400F) and mold temperature of18.33° C. and injection speed of 25 cc/s. Extrusion processing ofcompounds was performed on a Haake single screw extruder with an annulardie (inner diameter (ID)=2.54 mm, wall thickness=0.42 mm). The extrudedtube profile was air-cooled on a conveyor. Once stabilized, headpressure and torque were measured at various RPMs ranging from 20 to160. Samples were collected at each RPM. Visual observations were madeon the surface roughness and shape retention of the collected samples.

Standard CRYSTAF Method

Branching distributions are determined by crystallization analysisfractionation (CRYSTAF™) using a CRYSTAF 200 unit commercially availablefrom PolymerChar, Valencia, Spain. The samples are dissolved in 1,2,4trichlorobenzene at 160° C. (0.66 mg/mL) for 1 hr and stabilized at 95°C. for 45 minutes. The sampling temperatures range from 95 to 30° C. ata cooling rate of 0.2° C./min. An infrared detector is used to measurethe polymer solution concentrations. The cumulative solubleconcentration is measured as the polymer crystallizes while thetemperature is decreased. The analytical derivative of the cumulativeprofile reflects the short chain branching distribution of the polymer.

The CRYSTAF peak temperature and area are identified by the peakanalysis module included in the CRYSTAF Software (Version 2001.b,PolymerChar, Valencia, Spain). The CRYSTAF peak finding routineidentifies a peak temperature as a maximum in the dW/dT curve and thearea between the largest positive inflections on either side of theidentified peak in the derivative curve. To calculate the CRYSTAF curve,the preferred processing parameters are with a temperature limit of 70°C. and with smoothing parameters above the temperature limit of 0.1, andbelow the temperature limit of 0.3.

Flexural/Secant Modulus

Samples are compression molded using ASTM D 1928. Flexural and 2 percentsecant moduli are measured according to ASTM D-790.

Differential Scanning calorimetry

Differential Scanning calorimetry results are determined using a TAImodel Q1000 DSC equipped with an RCS cooling accessory and anautosampler. A nitrogen purge gas flow of 50 ml/min is used. The sampleis pressed into a thin film, at 30000 psi for 5 minutes at 175° C., andthen air-cooled to room temperature (25° C.). The pressed sample (3-10mg) is then cut into a 6 mm diameter disk, accurately weighed, placed ina light aluminum pan (about 50 mg), and then crimped shut. The thermalbehavior of the profile compositions samples is investigated with thefollowing temperature profile. The sample is rapidly heated to 230° C.and held isothermal for 3 minutes, in order to remove any previousthermal history. The sample is then cooled to −90° C., at 10° C./mincooling rate, and held at −90° C. for 3 minutes. The sample is thenheated to 230° C., at 10° C./min. heating rate. The cooling and secondheating curves are recorded. The temperature of crystallization is notedas Tc (° C.).

The DSC melting peak is measured as the maximum in heat flow rate (W/g)with respect to the linear baseline drawn between −40° C. and end ofmelting. The heat of fusion is measured as the area under the meltingcurve between −40° C. and the end of melting using a linear baseline.

For olefin block copolymers or ethylene/α-olefin interpolymers, insteadof cooling to −90 C, cooling to −40° C., and, instead of heating to 230°C., heating to 150° C. is done.

The DSC melting peak is measured as the maximum in heat flow rate (W/g)with respect to the linear baseline drawn between −30° C. and end ofmelting. The heat of fusion is measured as the area under the meltingcurve between −30° C. and the end of melting using a linear baseline.

Calibration of the DSC is done as follows. First, a baseline is obtainedby running a DSC from −90° C. without any sample in the aluminum DSCpan. Then 7 milligrams of a fresh indium sample is analyzed by heatingthe sample to 180° C., cooling the sample to 140° C. at a cooling rateof 10° C./min followed by keeping the sample isothermally at 140° C. for1 minute, followed by heating the sample from 140° C. to 180° C. at aheating rate of 10° C. per minute. The heat of fusion and the onset ofmelting of the indium sample are determined and checked to be within0.5° C. from 156.6° C. for the onset of melting and within 0.5 J/g from28.71 J/g for the of fusion. Then deionized water is analyzed by coolinga small drop of fresh sample in the DSC pan from 25° C. to −30 C at acooling rate of 10° C. per minute. The sample is kept isothermally at−30° C. for 2 minutes and heat to 30° C. at a heating rate of 10° C. perminute. The onset of melting is determined and checked to be within 0.5°C. from 0° C.

Calculation of Percent Crystallinity

The percent crystallinity is calculated by dividing the heat of fusion(ΔHf), determined from the second heat curve, by a theoretical heat offusion of 292 J/g for PE (165 J/g, for PP (propylene basedpolymers−majority weight percent polymerized propylene)), andmultiplying this quantity by 100 (for example, % cryst.=(ΔHf/292J/g)×100 (for PE (ethylene based polymers−majority weight percentpolymerized ethylene)). The melting point(s) (Tm) of each polymer sampleis determined from the second heat curve obtained from DSC, as describedabove. The crystallization temperature (Tc) is measured from the firstcooling curve

GPC Method

For Gel Permeation Chromatography (GPC) measurements, thechromatographic system used is a Polymer Laboratories Model PL-210. Thecolumn and carousel compartments were operated at 145° C. Four PolymerLaboratories 20-um Mixed-A LS columns were used, with a solvent of 1,2 4Trichlorobenzene (TCB). The samples were prepared at a concentration of0.1 g of polymer in 50 ml of solvent. The solvent contained 200 ppm ofthe antioxidant butylated hydroxytoluene (BHT). Samples were prepared byagitating lightly for 1-2 hours at 160° C. The injection volume was 200microliters and the flow rate was 1.0 ml/min. Calibration of the GPCcolumn set was performed with narrow molecular weight distributionpolystyrene standards purchased from Varian Inc. (previously PolymerLaboratories). The polystyrene standard peak molecular weights wereconverted to polyethylene molecular weights using Williams, T., and I.M. Ward, “The Construction of Polyethylene Calibration Curve for GelPermeation Chromatography Using Polystyrene Fractions”, J. Polym. Sci.Polym. Lett., 6, 631 (1968): M_(polyethylene)=0.431(M_(polystyrene)).

Polyethylene equivalent molecular weight calculations are performedusing Viscotek TriSEC software Version 3.0.

ATREF Analysis

Analytical temperature rising elution fractionation (ATREF) analysis isconducted according to the method described in U.S. Pat. No. 4,798,081,and Wilde, L.; Ryle, T. R.; Knobeloch, D. C.; Peat, I. R.; Determinationof Branching Distributions in Polyethylene and Ethylene Copolymers, J.Polym. Sci., 20, 441-455 (1982), which are both incorporated byreference herein, in their entirety. The composition to be analyzed isdissolved in trichlorobenzene, and allowed to crystallize in a columncontaining an inert support (stainless steel shot), by slowly reducingthe temperature to 20° C., at a cooling rate of 0.1° C./min. The columnis equipped with an infrared detector. An ATREF chromatogram curve isthen generated by eluting the crystallized polymer sample from thecolumn, by slowly increasing the temperature of the eluting solvent(trichlorobenzene) from 20 to 120° C., at a rate of 1.5° C./min.

¹³C NMR Analysis

The samples are prepared by adding approximately “3 g of a 50/50 mixtureof tetrachloroethane-d²/orthodichlorobenzene” to “0.4 g sample” in a 10mm NMR tube. The samples are dissolved and homogenized by heating thetube and its contents to 150° C. The data are collected using a JEOLEclipse™ 400 MHz spectrometer or a Varian Unity Plus™ 400 MHzspectrometer, corresponding to a ¹³C resonance frequency of 100.5 MHz.The data are acquired using 4000 transients per data file with a 6second pulse repetition delay. To achieve minimum signal-to-noise forquantitative analysis, multiple data files are added together. Thespectral width is 25,000 Hz with a minimum file size of 32K data points.The samples are analyzed at 130° C. in a 10 mm broad band probe. Thecomonomer incorporation is determined using Randall's triad method(Randall, J. C.; JMS-Rev. Macromol. Chem. Phys., C29, 201-317 (1989),which is incorporated by reference herein in its entirety).

Stress-Strain

Stress-strain behavior in uniaxial tension is measured using ASTM D 1708microtensile specimens. Samples are stretched with an Instron at 500%min⁻¹ at 21° C. Tensile strength and elongation at break are reportedfrom an average of 5 specimens. Type C tear was measured using ASTM-882.

Block Index

The ethylene/α-olefin multiblock copolymers are characterized by anaverage block index, ABI, which is greater than zero and up to about 1.0and a molecular weight distribution, M_(w)/M_(n), greater than about1.3. The average block index, ABI, is the weight average of the blockindex (“BI”) for each of the polymer fractions obtained in preparativeTREF (i.e., fractionation of a polymer by Temperature Rising ElutionFractionation) from 20° C. and 110° C., with an increment of 5° C.(although other temperature increments, such as 1° C., 2° C., 10° C.,also can be used):ABI=Σ(w _(i)BI_(i))

where BI_(i) is the block index for the ith fraction of the inventiveethylene/α-olefin interpolymer obtained in preparative TREF, and w_(i)is the weight percentage of the ith fraction. Similarly, the square rootof the second moment about the mean, hereinafter referred to as thesecond moment weight average block index, can be defined as follows.

2^(nd) moment weight average

${{BI} = \sqrt{\frac{\sum\;\left( {w_{i}\left( {{BI}_{i} - {ABI}} \right)}^{2} \right)}{\frac{\left( {N - 1} \right){\sum\; w_{i}}}{N}}}},$

where N is defined as the number of fractions with BI_(i) greater thanzero.

BI is defined by one of the two following equations (both of which givethe same BI value):

${{BI} = {{\frac{{1/T_{X}} - {1/T_{XO}}}{{1/T_{A}} - {1/T_{AB}}}\mspace{14mu}{or}\mspace{14mu}{BI}} = {- \frac{{LnP}_{X} - {LnP}_{XO}}{{LnP}_{A} - {LnP}_{AB}}}}},$

where T_(X) is the ATREF (i.e., analytical TREF) elution temperature forthe ith fraction (preferably expressed in Kelvin), P_(X) is the ethylenemole fraction for the ith fraction, which can be measured by NMR or IRas described below. P_(AB) is the ethylene mole fraction of the wholeethylene/α-olefin interpolymer (before fractionation), which also can bemeasured by NMR or IR. T_(A) and P_(A) are the ATREF elution temperatureand the ethylene mole fraction for pure “hard segments” (which refer tothe crystalline segments of the interpolymer). As an approximation orfor polymers where the “hard segment” composition is unknown, the T_(A)and P_(A) values are set to those for high density polyethylenehomopolymer. T_(AB) is the ATREF elution temperature for a randomcopolymer of the same composition (having an ethylene mole fraction ofP_(AB)) and molecular weight as the olefin block copolymer. T_(AB) canbe calculated from the mole fraction of ethylene (measured by NMR) usingthe following equation:Ln P _(AB) =α/T _(AB)+β

where α and β are two constants which can be determined by a calibrationusing a number of well characterized preparative TREF fractions of abroad composition random copolymer and/or well characterized randomethylene copolymers with narrow composition. It should be noted that αand β may vary from instrument to instrument. Moreover, one would needto create an appropriate calibration curve with the polymer compositionof interest, using appropriate molecular weight ranges and comonomertype for the preparative TREF fractions and/or random copolymers used tocreate the calibration. There is a slight molecular weight effect. Ifthe calibration curve is obtained from similar molecular weight ranges,such effect would be essentially negligible. In some embodiments, randomethylene copolymers and/or preparative TREF fractions of randomcopolymers satisfy the following relationship:Ln P=−237.83/T _(ATREF)+0.639.

The above calibration equation relates the mole fraction of ethylene, P,to the analytical TREF elution temperature, T_(ATREF), for narrowcomposition random copolymers and/or preparative TREF fractions of broadcomposition random copolymers. T_(XO) is the ATREF temperature for arandom copolymer of the same composition (i.e., the same comonomer typeand content) and the same molecular weight and having an ethylene molefraction of P_(X). T_(XO) can be calculated from “Ln PX=α/T_(XO)+β” froma measured P_(X) mole fraction. Conversely, P_(XO) is the ethylene molefraction for a random copolymer of the same composition (i.e., the samecomonomer type and content), and the same molecular weight, and havingan ATREF temperature of T_(X), which can be calculated from LnP_(XO)=α/T_(X)+β using a measured value of T_(X). Once the block index(BI) for each preparative TREF fraction is obtained, the weight averageblock index, ABI, for the whole polymer can be calculated.

Thermal Mechanical Analysis

Thermal Mechanical Analysis (TMA) (Penetration Temperature) is conductedon injection molded plaques. The instrument used was a TMA 7™ availablefrom Perkin-Elmer. In the test, a probe with 1.5 mm radius tip (P/NN519-0416) is applied to the surface of the sample with 1N force. Thetemperature is raised at 5° C./min from 25° C. The probe penetrationdistance is measured as a function of temperature. The experiment endswhen the probe has penetrated 1000 μm (1 mm) into the sample and all TMAtemperatures are reported for a penetration depth of 1000 μm.

Dynamic Mechanical Spectroscopy

Rheology was measured using Dynamic Mechanical Spectroscopy (DMS). DMSexperiments were conducted at 190° C. on a Rheometrics ARES equippedwith 25 mm parallel plates. Sample discs (25 mm in diameter) were cutfrom the injection molded plaques and nitrogen purge. The frequency wasvaried between 0.1 and 100 rad/s. The strain amplitude was adjustedbased upon the response of the samples between 4 and 10%. Rheology ratio(RR) was calculated as the ratio of the complex viscosity at 0.1 rad/sto complex viscosity at 100 rad/s. The tan δ which is a ratio of theloss modulus (G″) to the storage modulus (G′) was characterized at 0.1rad/s.

Calculation of the Shape Retention Index (SRI)

All compounds are subjected to a DMS-Temperature Ramp Experiment from90° C. to 190° C. in a parallel plate configuration on an ARESinstrument from Rheometric Scientific using 25 mm parallel plategeometry at a frequency of 1 rad/s and a strain between 4 to 10% that isauto-adjusted to prevent overtorquing. log of tan delta is plotted as afunction of log complex viscosity for a temperature range typically usedin extrusion processes such as from 130° C. to 190° C. A straight linecan be fit to this log tan delta vs. log complex viscosity plot, and theequation of the straight line, by linear regression in MICROSOFT OFFICEEXCEL 2003, can then be extrapolated from 1 to 5 on a log viscositycurve to determine the value of the tan(delta) at any viscosity. Anideal profile composition should possess low viscosities to extrude athigh line speeds without melt fracturing the surface of the profile.Also, to prevent collapse of the profile, these compounds should possesslow tan(delta). Shape retention index, SRI, is defined as the value oftan(delta) at a particular viscosity as determined by theDMS—temperature ramp extrapolations described above: SRI=tan(delta) at aparticular viscosity in the range of 100-10000 Pa s. 25 mm diameter discsamples for the DMS testing were punched out from injection moldedplaques with overall dimensions of 10.16 cm by 15.24 cm by 0.32 cm.

Density

Density (g/cm³) was measured according to ASTM-D 792-03, Method B, inisopropanol. Specimens were measured within 1 hour of molding afterconditioning in the isopropanol bath at 23° C. for 8 minutes, to achievethermal equilibrium prior to measurement. The test specimens werecompression molded according to ASTM D-4703-00 Annex A with a 5 mininitial heating period at about 190° C. and a 15° C./min cooling rateper Procedure C. The specimen was cooled to 45° C. in the press withcontinued cooling until “cool to the touch.”

Melt Indices and Melt Flow Rate

Melt index (I₂) of an ethylene-based polymer is measured in accordancewith ASTM D-1238-04, condition 190° C./2.16 kg. Melt index (I₅) of anethylene-based polymer is measured in accordance with ASTM D-1238-04,condition 190° C./5.0 kg. Melt index (I₁₀) of an ethylene-based polymeris measured in accordance with ASTM D-1238-04, condition 190° C./10.0kg. High load melt index (I₂₁) of an ethylene-based polymer is measuredin accordance with ASTM D-1238-04, condition 190° C./21.0 kg. Forpropylene-based polymers, the melt flow rate (MFR) is measured inaccordance with ASTM D-1238-04, condition 230° C./2.16 kg.

Shore A Hardness

Shore A hardness was measured per ASTM D2240 on injection molded plaquesof 0.32 cm thickness. This test method permits hardness measurementsbased on either initial indentation or indentation after a specifiedperiod of time, or both. As used herein, the indentation was measured ata specified time of 10 seconds.

Tensile and Elongation Properties

Tensile strength and elongation at break was measured using ASTM D 1708which is a micro-tensile method with a pull rate of 5 inches/minute inthe flow direction of the injection molded plaque. The dimensions of theinjection molded plaque were 101.6 mm×152.4×3.2 mm.

Compression Set

Compression set was measured according to ASTM D-395 at 23° C., 40° C.and 70° C. The sample was prepared by stacking 25.4 mm diameter rounddiscs cut from 0.125 inch thick injection molded plaques until a totalthickness of 12.7 mm is reached. Injection molding was carried out on anArburg 370C-80 ton injection molder using a plaque mold that is 101.6mm×152.4×3.2 mm. Typical process conditions for sample preparationinclude the following: Barrel and Mold Temperatures, zones 1 through 4and nozzle at 205° C. and mold at 15° C.; Extruder conditions of RPM 30(m/min), back pressure of 15 bar, dosage of 70 cubic centimeters (cc),and real dosage of 72 cc; Optimal Injection parameters of injectionspeed of 25 cc/seconds, transfer position of 15 cc, pressure at transferof 327 bar, fill time of 2.37 seconds, and cushion of 7.1 cc; holdconditions of pressure at 300 bar; hold time of 40 seconds, cool time of20 seconds, dosage time of 7.2 seconds and a cycle time of 68.8 seconds.In some cases, compression set after 24 hours (h) at 40° C. or 60° C. at25% strain is reported based on ISO 815-Type B method using 13 mm rounddisks, 6 mm thick. Samples cut from injection molded plaques (0.125″thick) are stacked up to a thickness of 6 mm.

Normalized Oil Bleed Index

Normalized oil-bleed index (NOBI) is an optical measurement to compareoil-bleed characteristics. Molded plaques are aged for 3 weeks (at 23°C. and 70° C.) while resting on sheets of ZigZag™ cigarette paper. Afteraging, the cigarette paper is removed and optically scanned against ablack background to measure the extent of oil-bleed. The scanning isperformed using the Xerox WorkCentre™ M118i copier/fax/scanner. Theimage is scanned in “Text” mode at 200 dpi, and saved as a TIFF file.The TIFF file is opened in MS Paintbrush, cropped on two sides, thensaved. The image is then opened in Photoshop CS2 (v.9) and cropped onthe other two sides. It is then converted to an 8-bit grayscale image sothat a grayscale histogram can be created. The grayscale image is thenanalyzed using the Photoshop software to create a histogram showing thepercentile of each of 4 quadrants of grayscale, ranging from 0 (black)to 255 (white). The average grayscale percentile is recorded. Forexample, if 1% of the pixels are in the 0-64 level of grayscalequadrant, and 3% of the pixels are in the 65-128 level of grayscalequadrant, and 15% are in the 129-192 level of grayscale quadrant, and31% are in the 193-255 level of grayscale quadrant, the systemcalculates the average to be 12.5%. A normalized oil-bleed index (NOBI)is calculated according to the following equation:Normalized Oil-bleed Index=100·(% grayscale sample−% grayscalecontrol)/(100−% grayscale control).The term “% grayscale sample” is the percent grayscale measured on theaged sample and “% grayscale control” is a measurement on an unageduntreated sheet of cigarette paper. NOBI has a range from 0 to 100. WhenNOBI=100, the paper is saturated and the test does not registeroil-bleed beyond that level.Tack Force

The tack force was measured using a ChemInstruments EZ Lab, CompatibleLoop Tack Tester (Model LT-1000). The test sample was an injectionmolded or compression molded bar “4 inch×6 inch×0.125 inch.” For eachpolymer composition, five bars were tested, and an average recorded.

The test bars were conditioned at 70° C. for seven days, in a forced airconvention oven, before being tested for tack. The test method was basedon a modified version of ASTM D6195-03, “Standard Test Methods for LoopTack” (Reference: 3 Annual Book of ATSM Standards, Vol 15.06.). For eachtest, a bar was placed in the lower brace of the loop tack tester. Astrip of “5 mil thick” MYLAR (1 inch×6 inch) was cut, using a “1 inch×6inch” die. The end of the MYLAR strip was trimmed to form a “1 inch×5inch” strip. The MYLAR strip was folded into a loop, with the glossyside as the exterior side, and place in the top grip of the Loop Tacktester. The exterior surface of the loop was brought into controlledcontact with a “1 inch×1 inch” surface of test bar specimen, with theonly force applied being the weight of the MYLAR strip itself. The MYLARstrip was then removed from the substrate, and the force to remove theMYLAR strip from the contacting surface was measured by a recordinginstrument.

Mooney Viscosity

Polymer Mooney viscosity (ML 1+4 at 125° C.) was measured in accordancewith ASTM 1646-04, with a one minute preheat time and a four minuterotor operation time. The instrument is an Alpha Technologies RheometerMDR.

EXAMPLES

The following examples illustrate the present invention but are notintended to limit the scope of the invention. The weight percent of thecomponents of each of the inventive and comparative examples are basedon the total formulation weight, unless stated otherwise.

Table 1 lists components used in preparing the Inventive and ComparativeExamples. NORDEL IP Hydrocarbon Rubbers, ENGAGE Polyolefin Elastomers,VERSIFY Elastomers and Plastomers and INFUSE Olefin Block Copolymers areavailable from The Dow Chemical Company; PROFAX resins are availablefrom Lyondellbasell Industries N.V. (Rotterdam, Netherlands), andLUPEROX compounds are organic peroxides available from Arkema, Inc.(Philadelphia, Pa.).

TABLE 1 Mooney Viscosity or Tan I₂ (g/10 Rheology delta @ min) or Ratio0.1 MFR (g/10 Density Crystallinity (V0.1/V100), rad/s. Tc Polymer Typemin) (g/cc) (wt %) 190° C. 190° C. (° C.) NORDEL EPDM 70 Mooney 0.88 1332 1.3 34 IP 4770 NORDEL EPDM 60 Mooney 0.87 12 35 1.06 12 IP 3760NORDEL EPDM 25 Mooney 0.88 12 20 1.70 36 IP 4725 NORDEL EPDM 20 Mooney0.88 14 15 2.4 43 IP 3720 OBC-00 EO-OBC* 0.5 0.877 18 7 6.0 98 OBC-07EO-OBC 0.5 0.866 9.5 7 6.0 89 OBC-507 EO-OBC 5.0 0.866 — — — — OBC-1EO-OBC 0.13 0.877 18.0 16 3.13 98 OBC-2 EO-OBC 0.2 0.878 18.0 26 — 101OBC-3 EO-OBC 0.15 0.870 9.0 25 — 100 OBC-4 Peroxide — 0.877 18.0 39 1.1798 modified OBC-1** OBC-5 Peroxide — 0.877 18.0 85 0.64 98 modifiedOBC-1*** OBC-6 Peroxide — — 33 1.04 98 modified OBC- 07**** OBC-7E-beamed — 0.866 10.0 43 0.93 90 OBC-07 with 2.1 MRad dosage OBC-8Ethylene/propylene I₂ = 0.15 0.866 8.9 12.3 2.2 76 OBC VERSIFY PropyleneBased MFR = 2 0.865 10.0 10.0 4.6 28.0 2300 Elastomer (PBE) VERSIFYPropylene Based MFR = 2 0.858 — — — — 2400 Elastomer (PBE) PropyleneHigh melt strength Mooney = 0.865 10.0 32 1.70 28.0 based (HMS) 50elastomer PBE (PBE)-1 ENR 6386 HMS Mooney = 0.875 18.0 56 1.1 45Ethylene/propylene 26 copolymer ENGAGE HMS I₂ = 0.2 0.87 HM 7387ethylene/butene copolymer EXP-21 Peroxide-modified — — — — — —ethylene/octene/ polypropylene blend LDPE 662i LDPE I₂ = 0.5 5E16S hPPMFR = 35 PROFAX E-beam hPP MFR = 2.5 PF814 7021-50 rcPP MFR = 50 PROFAXhPP 0.5 MFR  6823 PROFAX PD hPP 35 MFR 702 D221 hPP 35 MFR DMDA 8920HDPE I₂ = 20 0.954 — — — — *Ethylene/octene multiblock copolymer.**Modified with 0.05 wt % Luperox 101 and 0.05 wt % SR350. ***Modifiedwith with 0.1 wt % Luperox 101 and 0.1 wt % SR350 co-agent. ****Peroxidemodified OBC-07 (69 wt %) and hPP 5A10 (1.2 MFR) with 0.05 wt % LUPEROX101 and 0.05 wt % SR350.

In each of Tables 2-6, the component polymers are given in weightpercentages. Calcium carbonate available from Imerys PerformanceMinerals under the mark ATOMITE, and MB50-002 (a masterbatch ofpelletized formulation containing 50% of an ultra-high molecular weight,siloxane polymer dispersed in polyethylene (LDPE) homopolymer),available from Dow Corning under the name MB50-002 MASTERBATCH, wereused in the inventive and comparative examples in Tables 2-6.

The term “NM,” as used in all tables herein means “not measured.”

Tables 2A-2B below provides the formulations and observed properties forInventive Example (“Inventive Ex.”) 1 and Comparative Examples(“Comparative Ex.”) A-D, respectively. Each of the formulations inTables 2A-2B contains 15 wt % oil. Tensile properties, shown in Tables2A-2B, were measured per ASTM D638 (508 mm/sec pull rate). Black colorconcentrate used is available from Americhem, Inc. sold under the nameESCORENE AN13K.

TABLE 2A Inventive Ex. 1 NORDEL IP 4770, wt % 45.7 5E16S PP, wt % 16.8PARALUX 6001R Oil, wt % 15 CaCO_(3,) wt % 20 MB50-002 0.5 MASTERBATCH,wt % ESCORENE AN13K, wt % 2 Hardness Shore A NM Density (g/cc) 1.03 Ult.Tensile (MPa) 7.7 Ult. Elongation (%) 568 Tear Strength 54 Die C (N/mm)Comp. Set (CS) % @ 35 23° C. Comp. Set (CS) % @ 57 70° C. Melt fractureNone at up to 160 rpm Torque data NM Shape retention Yes TMA (° C. at1000 μm) 97 Tc (° C.) 89 Overall acceptability* Yes SRI at 1000 Pa s1.25 SRI at 10000 Pa s 0.95 *The term “overall acceptability,” as usedherein, indicates whether the sample possessed the inventive propertiesof shape retention, as well as the inventive balance of Shore A hardnessand compression set at 40° C. and/or at 70° C. In addition, theinventive compositions show no melt fracture at 160 rpm.

TABLE 2B Comparative Comparative Comparative Comparative Ex. A Ex. B Ex.C Ex. D ENX 8921, wt % 62.5 ENR 6386, wt % 46.9 OBC-00, wt % 46.9 46.9LDPE 662i, wt % 15.6 PROFAX PF814 PP, wt % 0 15.6 15.6 PARALUX 6001ROil, wt % 15 15 15 15 CaCO₃ wt % 20 20 20 20 MB50-002, 0.5 0.5 0.5 0.5MASTERBATCH, wt % ESCORENE AN13K, wt % 2 2 2 2 Hardness Shore A 82 74 6373 Density (g/cc) 0.98 1.01 0.99 1.01 Ult. Tensile (MPa) 5.7 5.7 7.4 9.3Ult. Elongation (%) 500 330 980 930 Tear Strength 37.3 25.2 33.6 45.7Die C (N/mm) Compression Set % @ 32 42 33 33 23° C. (ASTM) CompressionSet % @ 87 77 50 50 70° C. (ASTM) Melt fracture None at up None at upMelt Melt to 160 rpm to 160 rpm fracture fracture @ 40 rpm+ @ 40 rpm+Torque data 2000 mg at 2700 mg at 3500 mg at 3500 mg at 160 rpm 160 rpm160 rpm 160 rpm Shape retention Yes Yes No No TMA (° C. at 1000 μm) 100120 103 122 Tc (° C.) 134 110 130 120 Overall acceptability No (CS No(CS No No poor) poor) SRI at 1000 Pa s 1.25 2.27 6.6 5.3 SRI at 10000 Pas 0.78 1.00 2.19 2.2

Tables 2A and 2B illustrate that Inventive Example 1 exhibits tensile,elongation, and compression properties which meet the criteria foroverall acceptability. In contrast, the Comparative Examples do not meetthe requirements for overall acceptability. Comparative Examples C and Ddo not meet the inventive SRI requirements and Comparative Examples Aand B do not meet the inventive compression set requirements. Tables3A-3B provide the formulations and observed properties for InventiveExamples 2-5 and Comparative Example E, respectively. Each of theformulations in Tables 3A-3B include 25 wt % Oil.

TABLE 3A Inventive Inventive Inventive Inventive Ex. 2 Ex. 3 Ex. 4 Ex. 5NORDEL IP 4770, wt % 39.4 19.7 29.7 29.7 OBC-8, wt % — 19.7 — — SEBSKRATON 1651, wt % — — — 10 SANTOPRENE 101-64 TPV, — — 10 — wt % D221-35MFR PP, wt % — — 13.1 13.1 PROFAX PD702 (35 MFR 13.1 13.1 — — PP), wt %TiO₂, wt % 2 2 2 2 PARALUX 6001R Oil, wt % 25 25 25 25 CaCO_(3.) wt % 2020 20 20 MB50-002 0.5 0.5 0.5 0.5 MASTERBATCH, wt % Shore A Hardness 7266 74 72 Density (g/cc) 1.03 1.02 1.03 1.0 Ult. Tensile (MPa) 5.8 4.336.0 7.26 Ult. Elongation (%) 615 676 632 658 Tear Strength (N/mm) 39.533.6 39.8 39.7 Compression Set (%) @ 37 36 — — 23° C. (ASTM) CompressionSet (%) @ 68 74 73.4 — 70° C. (ASTM) Compression Set (%) 65.3 54.2 64.359.3 40° C. (ISO) (25%, 24 h) Compression Set (%) 85.3 72.3 81.5 77.960° C. (ISO) (25%, 24 h) Melt Fracture No No No No Torque data at 160rpm NM NM 2200 2800 Shape retained Yes Yes Yes Yes Overall acceptabilityYes Yes Yes Yes TMA (° C. at 1000 μm) 80 97 — — Tc (° C.) 105 92 — — SRIat 1000 Pa s 1.6 2.5 2.3 2.2 SRI at 10000 Pa s 1.0 1.50 1.05 1.15

TABLE 3B Comparative Ex. E OBC-8, wt % 39.7 7021-50 (50 MFR RCP 13.1PP), wt % TiO₂, wt % 2 Oil, wt % 25 CaCO₃, wt % 20 MB50-002 0.5MASTERBATCH, wt % Shore A Hardness 60 Density (g/cc) 1.03 Ult. Tensile(MPa) 3.4 Ult. Elongation (%) 809 Tear Strength (N/mm) 25.0 CompressionSet (%) at — 23° C. (ASTM) Compression Set (%) at — 70° C. (ASTM)Compression Set (%) at 40° C. (ISO) (25%, 24 h) Compression Set (%) at —60° C. (ISO) (25%, 24 h) Melt Fracture Yes Torque data at 160 rpm 3000Shape retained No Overall acceptability No TMA (° C. at 1000 μm) 113 Tc(° C.) 92 SRI at 1000 Pa s 4.15 SRI at 10000 Pa s 2.27

The Inventive Examples and Comparative Examples shown in Tables 3A and3B illustrate that the addition of SEBS or OBC to EDPM formulations canreduce the high temperature Compression Set in comparison toformulations that include only EDPM, oil and filler. As can be seen inthe Table 3A, each of the Inventive Examples meet the inventiverequirements for overall acceptability. Table 3B illustrates thatComparative Example E does not meet, at least, the SRI requirements foran inventive composition.

Tables 4A-4B provide the formulations and observed properties forInventive Examples 6-7 and Comparative Examples F-H, respectively.

TABLE 4A Inventive Inventive Ex. 6 Ex. 7 NORDEL IP 4770, wt % — 34.4OBC-7, wt % 39.4 — 5E16S-35 MFR PP, wt % 13.1 — PROFAX PD702 (35 MFR —13.1 PP), wt % TiO₂, wt % 2 2 PARALUX 6001 R Oil, wt % 25 30 CaCO_(3,)wt % 20 20 MB50-002 0.5 0.5 MASTERBATCH, wt % Density (g/cc) NM 1.03Ult. Tensile (MPa) 2.88 6.07 Ult. Elongation (%) 1294 666 Tear Strength(N/mm) NM 36.6 Compression Set (%) at 21 NM 23° C. (ASTM) CompressionSet (%) at 52 64 70° C. (ASTM) Compression Set (%) at NM 72.3 40° C.(ISO) Compression Set (%) at NM NM 60° C. (ISO) Melt Fracture No NoTorque at 160 rpm NM 2300 Shape retained Yes Yes Overall acceptabilityYes Yes T_(c) (° C.) — 126 SRI at 1000 Pa s 1.5 2.08 SRI at 10000 Pa s 11.27

TABLE 4B Comp. Comp. Comp. Ex. F Ex. G Ex. H NORDELIP 4770, wt % 39.3 —— OBC-07, wt % — 39.4 35.6 5E16S-35 MFR PP, wt % — 13.1 — PROFAX 6823(12 MFR) — — 11.83 PP, wt % PROFAX PD702 (35 MFR 13.13 — — PP), wt %TiO_(2,) wt % 2 2 2 PARALUX 6001 Oil, wt % 25 25 35 CaCO_(3,) wt % 20 2015 MB50-002 0.5 0.5 0.5 MASTERBATCH, wt % LUPEROX 101 0.05 — 0.047(crosslinker), wt % SR 350**, wt % 0.02 0 0.023 Density (g/cc) 1.03 NM0.99 Ult. Tensile (MPa) 5.7 2.15 4.08 Ult. Elongation (%) 428 1664 847Tear Strength (N/mm) 44 NM 27.4 Compression Set (%) at — 24 25.10 23° C.(ASTM) Compression Set (%) at 68 66 NM 70° C. (ASTM) Compression Set (%)at 59.4 NM 51.5 40° C. (ISO) (25%, 24 h) Compression Set (%) at 69.6 NM61.8 60° C. (ISO) (25%, 24 h) Melt Fracture No Yes No Torque at 160 rpmNM NM 2300 Shape retained Yes No No Overall acceptability Yes No No TMA(° C. at 1000 μm) 106 — — T_(c) (° C.) 125 — — SRI at 1000 Pa s 0.9324.10 2.85 SRI at 10000 Pa s 0.658 2.53 1.74 **SR350 indicatestrimethylolpropane trimethacrylate, a low volatility trifunctionalmonomer used as a co-agent during peroxide modification.

Table 4A illustrates that Inventive Examples 6 and 7 each meet theinventive compositional and overall acceptability requirements. Table 4Billustrates that Comparative Example F and H contain a vulcanizationagent and/or co-agent. Comparative Examples G and H do not meet, atleast, the inventive requirement of overall acceptability. Tables 5A-5Bprovide the formulations and observed properties for Inventive Examples8-10 and Comparative Examples I-M.

Tables 5A-5B provide the formulations and observed properties forInventive Examples 8-10 and Comparative Examples I-M.

TABLE 5A Inventive Inventive Inventive Ex. 8 Ex. 9 Ex. 10 OBC-2, wt %39.4 — — OBC-3, wt % — 39.4 — PBE-1, wt % — — 39.4 5E16S, wt % 13.1 13.113.1 CaCO_(3,) wt % 20 20 20 PARALUX 6001 R, wt % 25 25 25 TiO_(2,) wt %2 2 2 MB50-002 0.5 0.5 0.5 MASTERBATCH, wt % Compression Set (%) at 19.424.7 24.7 23° C. (25%, 22 h) (ASTM) Compression Set (%) at 45.8 57 55.970° C. (25%, 22 h) (ASTM) Hardness (ASTM) 72.7 65.5 76.8 Compression Set(%) at 30.3 — 44.6 40° C. (ISO) (25%, 24 h) Compression Set (%) at 36.7— 52.5 60° C. (ISO)(25%, 24 h) Avg. Tensile @ Break 6.19 4.81 8.76 (MPa)Avg. Ult. Elong (%) 764 702 702 TMA (° C. at 1000 μm) 123 114 119 Tc (°C.) 101 103 102 Torque @ 175 C. 2241 2301 2216 (160 rpm) Melt FractureNo No No Shape Retained Yes Yes Yes Overall acceptability Yes Yes YesSRI at 1000 Pa s 2.6 2.6 4.44 SRI at 10000 Pa s 1.44 1.41 1.45

TABLE 5B Comp. Comp. Comp. Comp. Comp. Ex. I Ex. J Ex. K Ex. L Ex. MOBC-00, wt % 39.4 — — — — OBC-4, wt % — 39.4 — — — OBC-5, wt %, — — 39.4— — OBC-1, wt % — — — 39.4 — VERSIFY 2300, wt % — — — — 39.4 5E16S (35MFR 13.1 13.1 13.1 13.1 13.1 PP), wt % CaCO₃, wt % 20 20 20 20 20PARALUX 6001R, wt % 25 25 25 25 25 TiO_(2,) wt % 2 2 2 2 2 MB50-002 0.50.5 0.5 0.5 0.5 MASTERBATCH, wt % Compression Set (%) at 20.2 23.1 25.519.4 25.7 23° C. (25%, 22 h) (ASTM) Compression Set (%) at 50.8 50.749.3 44.6 62.8 70° C. (25%, 22 h) (ASTM) Hardness (ASTM) 69.3 72.6 73.470.4 78.3 Compression Set (%) at 32.9 34.9 — — — 40° C. (ISO) (25%, 24h) Compression Set (%) at 38.3 38.4 — — — 60° C. (ISO) (25%, 24 h) Avg.Tensile @ Break 5.32 5.14 4.53 6 10.3 (Mpa) Avg. Ult. Elongation (%) 843549 388 791 899 TMA (° C. at 1000 μm) 113 120 134 116 119 Tc (° C.) 102100 102 99 102 Torque @ 175° C. 2353 2538 2214 2810 1927 (160 rpm) MeltFracture No No Yes No No Shape Retained No Yes Yes Yes No Overall No YesNo No No acceptability SRI at 1000 Pa s 3.36 1.85 1.24 4.78 6.28 SRI at10000 Pa s 2.26 0.99 0.82 2.05 1.36

Table 5A illustrates that each of Inventive Examples 8-10 meet theinventive requirements of overall acceptability. Comparative Examples Jand K each contain peroxide modified OBCs (see Table 1). As can be seenin Table 5B Comparative Examples I, L and M do not meet, at least, theinventive requirement of overall acceptability.

Tables 6A-6B provide the formulations and observed properties forInventive Examples 11-13 and Comparative Examples N-Q, respectively.

TABLE 6A Inventive Inventive Inventive Ex. 11 Ex. 12 Ex. 13 NORDEL IP4770, wt % 39.4 — 39.4 NORDEL IP 3760, wt % — 39.4 — hPP 5E16S (35 MFRPP), 13.1 13.1 — wt % HDPE DMDA 8920, wt % 13.1 CaCO_(3,) wt % 20 20 20PARALUX 6001R, wt % 25 25 25 TiO_(2,) wt % 2 2 2 MB50-002 0.5 0.5 0.5MASTERBATCH, wt % Compression Set (%) at 31 52.8 31 23° C. (ASTM)Compression Set (%) at 82.3 79.7 60.1 70° C. (ASTM) Compression Set (%)at 62.7 — 64.0 40° C. (ISO)(25%, 24 h) Compression Set (%) at 86.1 —72.6 60° C. (ISO)(25%, 24 h) Shore A Hardness 67.5 49.8 69.0 Avg.Tensile @ Break (Mpa) 7.99 2.45 5.8 Av. Ult. Elong (%) 840 730 763 TMA(° C. at 1000 μm) 96 101 121 T_(c) (° C.) 82 80 110 Torque @ 175° C.2776 2992 3735 (160 rpm) Melt Fracture No No No Shape Retained Yes YesYes Overall acceptability Yes Yes Yes SRI at 1000 Pa s 1.79 1.85 3.9 SRIat 10000 Pa s 1.16 1.28 1.5

TABLE 6B Comparative Comparative Comparative Comparative Ex. N Ex. O Ex.P Ex. Q NORDEL IP 4725, wt % 39.4 NORDEL IP 3720, wt % 39.4 OBC-6, wt %52.5 D9007, wt % 36.7 hPP 700-12,* wt % 15.7 hPP 5E16S (35 MFR 13.1 13.10 0 PP), wt % CaCO₃, wt % 20 20 20 20 PARALUX 6001 R, wt % 25 25 25 25TiO_(2,) wt % 2 2 2 2 MB50-002 0.5 0.5 0.5 0.5 MASTERBATCH, wt % LUPEROX101, wt % 0.05 SR-350, wt % 0.05 Compression Set (%) at 39.2 36.4 27.127.3 23° C. (ASTM) Compression Set (%) at — — 60 60.4 70° C. (ASTM)Compression Set (%) at 69.5 — — — 40° C. (ISO) (25% at 24 hrs)Compression Set (%) at 85.2 — — — 60° C. (ISO) (25% at 24 hrs) Hardness64 62.3 64.8 67.3 Avg. Tensile @ Break 4.86 3.78 4.78 4.99 (Mpa) Avg.Ult. Elong (%) 793 724 699 726 TMA (° C. at 1000 μm) 83 71 123 128 T_(c)(° C.) 81 82 97 98 Torque @ 175° C. 2250 2374 2124 2199 (160 rpm) MeltFracture No No No No Shape Retained No No Yes No Overall acceptabilityNo No Yes Yes SRI at 1000 Pa s 2.03 2.43 1.91 2.19 SRI at 10000 Pa s 1.31.46 1.10 1.35 *hPP700-12 is a homopolypropylene (MFR = 12) availablefrom The Dow Chemical Company.

As seen in Table 6A, each of Inventive Examples 11-13 meet allrequirements of the inventive composition. Comparative Examples N and Odo not meet the inventive requirement of overall acceptability.Comparative Example P contains a peroxide modified OBC (see Table 1).Comparative Example Q was peroxide modified (see Table 1).

Table 7 provides the components for the formulations shown in Tables8-10. Table 8 provides the formulations for Inventive Examples 14-16 andComparative Examples R-S. Each of the Inventive and Comparative Examplesin Table 8 include 72.5 PHR oil. Table 9 provides the formulations forInventive Examples 17-19 and Comparative Examples T-U. Each of theInventive and Comparative Examples in Table 9 include 130 PHR oil. Table10 provides the formulations for Inventive Examples 20-22 andComparative Examples V-W. Each of the Inventive and Comparative Examplesin Table 10 include 190 PHR oil.

Table 11 provides the formulations of Inventive Examples 23-26 andComparative Examples X-Y. All quantities in Table 11 are in weightpercentages. Table 12 provides the extruder conditions for the samplesof the Inventive and Comparative Examples of Table 11 that were preparedon a ZSK-30 twin screw extruder with dual injector ports. Table 13provides the characteristics of Inventive Examples 23-26 and ComparativeExample X-Y.

TABLE 7 I₂, I₁₀, ΔHf, % Cry, Mn, Mw, % Ethylene, Mooney g/10 min g/10min I₁₀/I₂ (J/g) wt % g/mole g/mole Mw/Mn by NMR Viscosity† RR# R04*0.382 4.637 12.14 75.17 25.7 48,330 12,740 2.5 66.5 Less than 55 R07**1.305 34.4 11.8 61,270 188,300 3.07 65.8 70 30 R08*** 1.485 39.84 13.655,010 169,010 3.07 70.8 70 32 NORDEL IP 39.5 13.5 59,360 180,590 3.0470 70 32 4770^(a) NORDEL IP 41 14.0411 83,260 174,970 2.10 68 854785^(b) VISTAL- 13.7 4.7 >4 63 60 LON 3666## *R04 is a diene freesingle reactor EP containing 66 wt % ethylene and having an I₂ of 0.4g/10 min. **R07 is a diene free, single reactor, ethylene/propylenecopolymer (EP) containing 66 wt % ethylene and having a Mooney Viscosityof 70. ***R08 is a diene free single reactor EP containing 71 wt %ethylene and having a Mooney Viscosity of 70. †ML (1 + 4), 125° C.). #RRindicates the rheology ratio (V0.1/V100), 190 C. ##Oil extended polymer.^(a)Mooney Viscosity of 70 and 70 wt % Ethylene. ^(b)Mooney Viscosity of85 and 68 wt % Ethylene.

TABLE 8 Comp. Inv. Comp. Inv. Inv. Ex. R Ex. 14 Ex. S Ex. 15 Ex. 16 R07,wt % 37.2 R08, wt % 37.2 R04, wt % 37.2 NORDEL IP 4770, wt % 37.2 NORDELIP 4785, wt % 37.2 HDPE 8920, wt % 12.8 12.8 12.8 12.8 12.8 Paralux Oil6001R, wt % 27 27 27 27 27 TiO2, wt % 2.5 2.5 2.5 2.5 2.5 MB50-002 0.50.5 0.5 0.5 0.5 MASTERBATCH, wt % Calcium Carbonate 20 20 20 20 20(Atomite), wt % Formulation properties Compression Set (%) at 38.6732.71 41.66 30.07 30.42 23° C. (ASTM) Compression Set (%) at 55.17 61.4864.93 64.10 61.74 40° C. (ASTM) Compression Set (%) at 55.02 60.74 88.8469.39 74.86 70° C. (ASTM) Shore A Harness (10 s) 50.00 62.30 80.64 66.9059.66 Avg. 100% Mod 1.13 1.88 3.61 2.23 1.67 Avg. 2% Mod 0.04 0.07 0.380.08 0.05 Avg. 300% Mod 1.59 2.43 4.12 3.10 2.34 Avg. Tensile at Break2.09 3.33 5.14 4.28 3.26 Avg. Ult. Elongation 737.34 714.24 656.08635.32 676.07 NOBI*, 23° C. 0.00 4.14 100.00 0.00 0.00 NOBI, 70° C. 6.780.00 1.95 2.36 0.00 Tack Force (N) 0.0318 0.00742 0.10403 0.007120.00763 Tack Force St. dev. (N) 0.01346 0.00065 0.06044 0.0075 0.00064Rheology Ratio 11.36 9.69 5.40 11.20 12.60 TMA (° C.) 118.49 119.63121.73 119.60 120.32 T_(c) (° C.) 109.5 109.8 109.8 108.5 108.3*Normalized Oil Bleed Index.

TABLE 9 Comp. Inv. Comp. Inv. Inv. Ex. T Ex. 17 Ex. U Ex. 18 Ex. 19 R07,wt % 27.0 R08, wt % 27.0 R04, wt % 27.0 NORDEL IP 4770, wt % 27.0 NORDELIP 4785, wt % 27 Hydrobrite 550, wt % 35.1 35.1 35.1 35.1 35.1 CaCO₃,(Atomite), wt % 27.0 27.0 27.0 27.0 27 HDPE 8920, wt % 10.8 10.8 10.810.8 10.8 Formulation properties Compression Set (%) at 38.54 37.1542.32 31.60 35.62 23° C. (ASTM) Compression Set (%) at 55.63 62.56 66.6069.90 67.47 40° C. (ASTM) Compression Set (%) at 67.65 70.07 80.42 76.4576.80 70° C. (ASTM) Shore A (10 s) 34.24 49.52 72.70 55.70 45.38 Avg.100% Mod 0.72 1.03 2.21 2.72 0.97 Avg. 2% Mod 0.02 0.03 0.13 0.05 0.02Avg. 300% Mod 1.07 1.46 2.59 3.87 1.43 Avg. Tensile at Break 1.39 2.153.61 5.89 2.06 Avg. Ult. Elongation 713.70 804.88 778.45 710.81 669.10NOBI, 23° C. 0.83 3.50 100.00 2.91 0.00 NOBI, 70° C. 1.81 6.45 47.593.75 0.00 Tack Force (N) 0.25521 0.00915 0.09969 0.00979 0.00701 TackForce St. Dev. (N) 0.21362 0.00187 0.0763 0.00728 0.00184 Rheology Ratio7.40 6.60 3.84 8.89 6.88 TMA (° C.) 105.5 107.4 118.8 114.4 111.6 T_(c)(° C.) 109.3 108.4 110.1 106 106

TABLE 10 Comp. Inv. Inv. Inv. Comp. Ex. V Ex. 20 Ex. 21 Ex. 22 Ex. WR07, wt % 22.5 R08, wt % 22.5 NORDEL IP 4770, wt % 22.5 NORDEL IP 4785,wt % 22.5 VISTALLON 3666 (EPDM 39.4 with 75 PHR oil), wt % Hydrobrite550, wt % 42.7 42.7 42.7 42.7 25.8 CaCO₃, (Atomite), wt % 22.5 22.5 22.522.5 22.5 HDPE 8920, wt % 12.3 12.3 12.3 12.3 12.3 FormulationsCompression Set (%) at 38.60 37.00 35.53 36.57 28.44 23° C. (ASTM)Compression Set (%) at 59.30 64.67 60.49 58.97 39.84 40° C. (ASTM)Compression Set (%) at 64.49 66.21 69.97 72.75 63.45 70° C. (ASTM) ShoreA (10 s) 30.12 50.36 58.80 51.28 40.76 Avg. 100% Mod 0.58 1.15 1.58 1.190.92 Avg. 2% Mod 0.02 0.03 0.05 0.04 0.02 Avg. 300% Mod 0.85 1.63 2.141.70 1.35 Avg. Tensile at Break 1.11 2.26 3.01 2.37 1.63 Avg. Ult.Elongation 724.49 740.12 701.36 675.31 650.22 NOBI, 23° C. 0.52 1.790.00 2.63 0.00 NOBI, 70° C. 8.92 0.00 0.00 11.73 0.00 Tack Force (N)0.59228 0.19186 0.00818 0.00967 0.00922 Tack Force St. Dev. (N) 0.404260.2066 0.00222 0.00241 0.00068 Rheology Ratio 6.25 6.09 7.57 6.28 45.96TMA (° C.) 99.82 117.42 T_(c) (° C.) 108 110 107 110 108

TABLE 11 Inv. Inv. Inv. Inv. Inv. Comp. Comp. Ex. X Ex. 22 Ex. 23 Ex. 24Ex. 25 Ex. 26 Ex. Y NORDEL IP 4770 19.6 23.3 24.4 25.6 27.0 28.6 30.3Hydrobrite 550 25.5 30.2 31.7 33.3 35.1 37.1 39.4 CaCO₃, (Atomite) 19.623.3 24.4 25.6 27.0 28.6 30.3 HDPE 8920 35.3 23.3 19.5 15.4 10.8  5.7 0.0

TABLE 12* Comp. Ex. X Inv. Ex. 22 Inv. Ex. 23 Inv. Ex. 24 Inv. Ex. 25Inv. Ex. 26 Comp. Ex. Y Zone 1 (° C.) 120/119 118 122 120 122 123 123Zone 2 (° C.) 175/166 160 168 169 171 168 169 Zone 3 (° C.) 170/171 164167 173 176 172 169 Zone 4 (° C.) 165/165 168 165 164 163 168 167 Zone 5(° C.) 160/166 161 168 168 165 164 164 Die Temp., ° C. 81 140/102 103102 106 104 99 Adaptor Temp., ° C. 122 150/143 148 149 150 153 152Pelletizer Speed (RPM) 2000 2000 2000 2000 1400 1400 1400 Die Pressure(psig) 1640 1340 1329 1282 1090 1560 1028 Extruder RPM 200 200 200 200200 200 200 Extruder Torque, % 60 54 56 53 48 52 42 Feeder #1 (lb/hr)15.7 11.3 10.1 9 739 6.8 5.6 Feeder #2 (lb/hr) 5.6 5 5.6 5.6 5.6 5.6 5.6Oil Injector 1, lb/hr 5.1 5.1 5.1 5.1 5.1 5.1 5.1 Oil Injector 2, lbs/hr2.2 2.2 2.2 2.2 2.2 2.2 2.2 Total Rate (lb/hr) 28.6 24.2 23 21.9 20.819.7 18.5 *Using a Model ZSK-30, a 30-mm screw diameter.

TABLE 13 Comp. Ex. X Inv. Ex. 22 Inv. Ex. 23 Inv. Ex. 24 Inv. Ex. 25Inv. Ex. 26 Comp. Ex. Y Compression Set 40° C. 54 55 55 55 58 62 67 (%)(ASTM) Compression Set 70° C. 51 51 51 46 57 62 85 (%) (ASTM) HardnessShore A (10 s) 91 82 79 75 65 57 41 Avg. 10% Stress (psi) 726 360 297191 89 39 22 Avg. 100% Stress (psi) 821 568 491 449 270 197 121 Avg. 2%Stress (psi) 132 73 63 35 15 5 4 Avg. 300% Stress (psi) 826 587 516 532309 232 165 Avg.Tensile at Break (psi) 1409 1242 1224 660 1014 988 1048Std. Dev. of Tensile at Break 41 50 34 33 30 113 27 Avg. Ult. Elong (%)1075 1137 1164 686 1267 1371 1466 Tack force (N) 0.01073 0.01017 0.010810.01024 0.01024 0.00979 0.01094 Tack force St. Dev. (N) 0.0073 0.001160.00206 0.00124 0.00104 0.00157 0.0015 NOBI, 23° C. 100.00 100.00 40.0716.11 12.55 2.34 32.77 NOBI, 70° C. 100.00 15.10 11.11 3.62 18.45 5.72*unable to peel sample

Comparative examples R, T and V use an EP rubber with delta H less than36 J/g with a tack force in the final article form IS greater than 0.012N that is unacceptable from a tack perception. Comparative Examples Sand U use an EP rubber with a Mooney viscosity close to 20, which isless than the preferred range of greater than 55. The NOBI for thesesamples, S and U, is unacceptable as such low Mooney polymers are unableto hold high levels of oil. Comparative Example W uses VISTALLON 3666containing 75 phr of oil that is supplied as a bale rather than pellets,and is not the preferred route for Thermoplastic Extrusion compounders.

Inventive Examples 14-22, on the other hand, are formulations containingethylene/α-olefin interpolymers having a ΔHf greater than 36 J/g, and aMooney viscosity greater than 55, and also containing an HDPE. Thesecompositions also have rheology ratio greater than 25. The InventiveExample formulations have the right balance of shore A hardness,compression set at elevated temperatures, low tack, low oil bleed,tensile strength, elongation, and TMA.

Comparative Example R exhibits a tack force that is too high (note thatthe ΔHf of R07 is 34 J/g ΔHf). Comparative Example S includes R04 whichhas a Mooney viscosity less than 55. Comparative Example S also had ahigh tack force.

Inventive Examples 22-26 are formulations with an EPDM having a ΔHfgreater than 36 J/g and a Mooney viscosity greater than 55 as componentA, and a HDPE as component B. These formulations also have a rheologyratio greater than 25. These inventive compositions exhibit theinventive balance of shore A hardness, compression set at elevatedtemperatures, low tack, low oil bleed, tensile strength and elongation.Comparative Example Y that has no HDPE and underwent a distortion inshape. Comparative Example X had NOBI values of 100 indicatingsignificant oil bleed. The remaining Comparative Examples did not havean optimum balance of properties.

Inventive Example 27 contained EPDM 1/HDPE 1 (75/25 or 3/1 ratio)+1 wt %PDMS (MB50-002) was prepared using a continuous mixer. The EPDM 1 had aMooney Viscosity (ML (1+4) at 125° C.) of 70, a ΔHf of 39.4 and a MWD of3.04. The HPDE 1 has a density of 0.954 g/cc and a melt index (I₂) of 20g/10 min.

Inventive Example 27 was formed in a Farrel CP 250 continuous mixer. Themixer was equipped with the 2.88 inch, 7/7 rotor combination with twodams at the 4 and 5 positions and a vent in the middle of the 7/8position. The EPDM 1 (74.25 wt %) and HDPE 1 (24.75%) and PDMS (MB50-002MASTERBATCH) (1%, based on the total composition weight)) were fed vialoss and weigh feeders, and the polymers were melted and compounded inthe mixer. The residence time was controlled by a feed rate at 300pounds per hour, orifice opening of 45-65%, and a mixer rotor speed of300-450 RPM. The mixer conditions are shown in Table 14.

TABLE 14 Mixer Conditions (Melt Temp. = 225° C.) Orifice Chamber BodyFeed Hopper Set Point Temp. (° C.) 150 150 50 Actual Temp. (° C.) 165142 99

Once polymers were mixed, the compounded ribbon was then fed into the 4inch 11/1 L/D extruder to be extruded into strands. A six hole stranddie was utilized. The strands were then run through a 16 foot water bathwith initial water temperature at 20° C., prior to cutting into pellets.The extruder conditions are shown in Table 15.

TABLE 15 Extruder Conditions (Melt Temp. = 223° C.) Die Heat AdapterForward Heat Rear Set Point Temp. (° C.) 210 210 210 210 Actual Temp. (°C.) 215 210 210 207

Some rheological properties of this example are listed in Table 16below.

TABLE 16 Phase Freq G′ G″ Eta* Temp Torque Strain G* Angle rad/s Pa PaPa-s tan_delta ° C. g-cm % Pa ° 0.1 4083.79 5242.94 66457.3 1.28384 19020.6942 9.95353 6645.73 52.084 0.15849 5438.59 6790.37 54892.4 1.24855189.99 27.0804 9.94977 8699.85 51.308 0.25119 7157.69 8759.15 45032.81.22374 190 35.191 9.9443 11311.7 50.745 0.39811 9353.63 11267.9 36784.81.20465 190 45.527 9.93737 14644.3 50.303 0.63096 12218.6 14566.530132.8 1.19216 190 59.0536 9.92835 19012.5 50.01 1 15932.6 18727.224587.7 1.1754 190 76.2756 9.91604 24587.7 49.61 1.58489 20783.6 23974.520019.7 1.15353 190 98.2651 9.8995 31729 49.078 2.51189 27177.7 30548.316277.8 1.12402 190 126.409 9.88217 40888 48.342 3.98107 35497.7 38571.513167.3 1.08659 190 161.668 9.8582 52419.9 47.376 6.30957 46306.948235.2 10597.4 1.04164 190.01 205.49 9.82337 66865.3 46.168 10 59830.859232.5 8419.15 0.99 190 257.635 9.78155 84191.5 44.712 15.8489 77295.872158.6 6671.91 0.93354 190 321.721 9.72524 1.06E+05 43.031 25.118999022.7 86512.8 5234.76 0.87367 190 397.365 9.6597 1.31E+05 41.14339.8107 1.25E+05 1.02E+05 4060.27 0.81191 190 484.048 9.57202 1.62E+0539.073 63.0957 1.58E+05 1.18E+05 3121.3 0.74935 190 582.897 9.460781.97E+05 36.846 100 1.94E+05 1.33E+05 2352.86 0.68636 190.01 685.4549.31222 2.35E+05 34.464

Inventive Example 27 has excellent rheological properties (for example,V0.1/V100=28), and good shear thinning behavior. This example also hadgood shape retention and control.

The present invention may be embodied in other forms without departingfrom the spirit and the essential attributes thereof, and, accordingly,reference should be made to the appended claims, rather than to theforegoing specification, as indicating the scope of the invention.

We claim:
 1. A thermoplastic composition comprising: i) component C, anethylene/α-olefin interpolymer wherein the interpolymer has a MooneyViscosity (ML 1+4, 125° C.) greater than, or equal to, 55 and a ΔHfgreater than, or equal to, 36 J/g; and ii) component D, a high densitypolyethylene (HDPE) wherein the HDPE has an I₂ from 1 to 50 g/10 min;and wherein the ethylene/α-olefin interpolymer is anethylene/α-olefin/diene interpolymer having a rheology ratio (V0.1/V100) at 190° C. greater than, or equal to
 25. 2. The thermoplasticcomposition of claim 1, wherein component C has a molecular weightdistribution (MWD) less than
 4. 3. The thermoplastic composition ofclaim 1, wherein the HDPE is present in an amount from 30 to 100 PHR,based on the weight of the ethylene/α-olefin interpolymer.
 4. Thethermoplastic composition of claim 1, further comprising an oil.
 5. Thethermoplastic composition of claim 1, further comprising a filler. 6.The thermoplastic composition of claim 1, wherein the composition has acompression set less than 70 percent, as measured by ASTM D-395 at 70°C.
 7. The thermoplastic composition of claim 1, wherein the compositiondoes not include a vulcanization agent or vulcanization co-agent.
 8. Anarticle comprising the composition of claim 1.